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@ -0,0 +1,107 @@
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底层 Linux 容器运行时之发展史
|
||||
======
|
||||
|
||||
> “容器运行时”是一个被过度使用的名词。
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||||
|
||||
|
||||
|
||||
在 Red Hat，我们乐意这么说，“容器即 Linux，Linux 即容器”。下面解释一下这种说法。传统的容器是操作系统中的进程，通常具有如下 3 个特性：
|
||||
|
||||
1. 资源限制
|
||||
|
||||
当你在系统中运行多个容器时，你肯定不希望某个容器独占系统资源，所以我们需要使用资源约束来控制 CPU、内存和网络带宽等资源。Linux 内核提供了 cgroup 特性，可以通过配置控制容器进程的资源使用。
|
||||
|
||||
2. 安全性配置
|
||||
|
||||
一般而言，你不希望你的容器可以攻击其它容器或甚至攻击宿主机系统。我们使用了 Linux 内核的若干特性建立安全隔离，相关特性包括 SELinux、seccomp 和 capabilities。
|
||||
|
||||
（LCTT 译注：从 2.2 版本内核开始，Linux 将特权从超级用户中分离，产生了一系列可以单独启用或关闭的 capabilities）
|
||||
|
||||
3. 虚拟隔离
|
||||
|
||||
容器外的任何进程对于容器而言都应该不可见。容器应该使用独立的网络。不同的容器对应的进程应该都可以绑定 80 端口。每个容器的<ruby>内核映像<rt>image</rt></ruby>、<ruby>根文件系统<rt>rootfs</rt>（rootfs）都应该相互独立。在 Linux 中，我们使用内核的<ruby>名字空间<rt>namespace</rt></ruby>特性提供<ruby>虚拟隔离<rt>virtual separation</rt></ruby>。
|
||||
|
||||
那么，具有安全性配置并且在 cgroup 和名字空间下运行的进程都可以称为容器。查看一下 Red Hat Enterprise Linux 7 操作系统中的 PID 1 的进程 systemd，你会发现 systemd 运行在一个 cgroup 下。
|
||||
|
||||
```
|
||||
# tail -1 /proc/1/cgroup
|
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1:name=systemd:/
|
||||
```
|
||||
|
||||
`ps` 命令让我们看到 systemd 进程具有 SELinux 标签：
|
||||
|
||||
```
|
||||
# ps -eZ | grep systemd
|
||||
system_u:system_r:init_t:s0 1 ? 00:00:48 systemd
|
||||
```
|
||||
|
||||
以及 capabilities：
|
||||
|
||||
```
|
||||
# grep Cap /proc/1/status
|
||||
...
|
||||
CapEff: 0000001fffffffff
|
||||
CapBnd: 0000001fffffffff
|
||||
CapBnd: 0000003fffffffff
|
||||
```
|
||||
|
||||
最后，查看 `/proc/1/ns` 子目录，你会发现 systemd 运行所在的名字空间。
|
||||
|
||||
```
|
||||
ls -l /proc/1/ns
|
||||
lrwxrwxrwx. 1 root root 0 Jan 11 11:46 mnt -> mnt:[4026531840]
|
||||
lrwxrwxrwx. 1 root root 0 Jan 11 11:46 net -> net:[4026532009]
|
||||
lrwxrwxrwx. 1 root root 0 Jan 11 11:46 pid -> pid:[4026531836]
|
||||
...
|
||||
```
|
||||
|
||||
如果 PID 1 进程（实际上每个系统进程）具有资源约束、安全性配置和名字空间，那么我可以说系统上的每一个进程都运行在容器中。
|
||||
|
||||
容器运行时工具也不过是修改了资源约束、安全性配置和名字空间，然后 Linux 内核运行起进程。容器启动后，容器运行时可以在容器内监控 PID 1 进程，也可以监控容器的标准输入/输出，从而进行容器进程的生命周期管理。
|
||||
|
||||
### 容器运行时
|
||||
|
||||
你可能自言自语道，“哦，systemd 看起来很像一个容器运行时”。经过若干次关于“为何容器运行时不使用 `systemd-nspawn` 工具来启动容器”的邮件讨论后，我认为值得讨论一下容器运行时及其发展史。
|
||||
|
||||
[Docker][1] 通常被称为容器运行时，但“<ruby>容器运行时<rt>container runtime</rt></ruby>”是一个被过度使用的词语。当用户提到“容器运行时”，他们其实提到的是为开发人员提供便利的<ruby>上层<rt>high-level</rt></ruby>工具，包括 Docker，[CRI-O][2] 和 [RKT][3]。这些工具都是基于 API 的，涉及操作包括从容器仓库拉取容器镜像、配置存储和启动容器等。启动容器通常涉及一个特殊工具，用于配置内核如何运行容器，这类工具也被称为“容器运行时”，下文中我将称其为“底层容器运行时”以作区分。像 Docker、CRI-O 这样的守护进程及形如 [Podman][4]、[Buildah][5] 的命令行工具，似乎更应该被称为“容器管理器”。
|
||||
|
||||
早期版本的 Docker 使用 `lxc` 工具集启动容器，该工具出现在 `systemd-nspawn` 之前。Red Hat 最初试图将 [libvirt][6] （`libvirt-lxc`）集成到 Docker 中替代 `lxc` 工具，因为 RHEL 并不支持 `lxc`。`libvirt-lxc` 也没有使用 `systemd-nspawn`，在那时 systemd 团队仅将 `systemd-nspawn` 视为测试工具，不适用于生产环境。
|
||||
|
||||
与此同时，包括我的 Red Hat 团队部分成员在内的<ruby>上游<rt>upstream</rt></ruby> Docker 开发者，认为应该采用 golang 原生的方式启动容器，而不是调用外部应用。他们的工作促成了 libcontainer 这个 golang 原生库，用于启动容器。Red Hat 工程师更看好该库的发展前景，放弃了 `libvirt-lxc`。
|
||||
|
||||
后来成立 <ruby>[开放容器组织][7]<rt>Open Container Initiative</rt></ruby>（OCI）的部分原因就是人们希望用其它方式启动容器。传统的基于名字空间隔离的容器已经家喻户晓，但人们也有<ruby>虚拟机级别隔离<rt>virtual machine-level isolation</rt></ruby>的需求。Intel 和 [Hyper.sh][8] 正致力于开发基于 KVM 隔离的容器，Microsoft 致力于开发基于 Windows 的容器。OCI 希望有一份定义容器的标准规范，因而产生了 [OCI <ruby>运行时规范<rt>Runtime Specification</rt></ruby>][9]。
|
||||
|
||||
OCI 运行时规范定义了一个 JSON 文件格式，用于描述要运行的二进制，如何容器化以及容器根文件系统的位置。一些工具用于生成符合标准规范的 JSON 文件，另外的工具用于解析 JSON 文件并在该根文件系统（rootfs）上运行容器。Docker 的部分代码被抽取出来构成了 libcontainer 项目，该项目被贡献给 OCI。上游 Docker 工程师及我们自己的工程师创建了一个新的前端工具，用于解析符合 OCI 运行时规范的 JSON 文件，然后与 libcontainer 交互以便启动容器。这个前端工具就是 [runc][10]，也被贡献给 OCI。虽然 `runc` 可以解析 OCI JSON 文件，但用户需要自行生成这些文件。此后，`runc` 也成为了最流行的底层容器运行时，基本所有的容器管理工具都支持 `runc`，包括 CRI-O、Docker、Buildah、Podman 和 [Cloud Foundry Garden][11] 等。此后，其它工具的实现也参照 OCI 运行时规范，以便可以运行 OCI 兼容的容器。
|
||||
|
||||
[Clear Containers][12] 和 Hyper.sh 的 `runV` 工具都是参照 OCI 运行时规范运行基于 KVM 的容器，二者将其各自工作合并到一个名为 [Kata][12] 的新项目中。在去年，Oracle 创建了一个示例版本的 OCI 运行时工具，名为 [RailCar][13]，使用 Rust 语言编写。但该 GitHub 项目已经两个月没有更新了，故无法判断是否仍在开发。几年前，Vincent Batts 试图创建一个名为 [nspawn-oci][14] 的工具，用于解析 OCI 运行时规范文件并启动 `systemd-nspawn`；但似乎没有引起大家的注意，而且也不是原生的实现。
|
||||
|
||||
如果有开发者希望实现一个原生的 `systemd-nspawn --oci OCI-SPEC.json` 并让 systemd 团队认可和提供支持，那么CRI-O、Docker 和 Podman 等容器管理工具将可以像使用 `runc` 和 Clear Container/runV （[Kata][15]） 那样使用这个新的底层运行时。（目前我的团队没有人参与这方面的工作。）
|
||||
|
||||
总结如下，在 3-4 年前，上游开发者打算编写一个底层的 golang 工具用于启动容器，最终这个工具就是 `runc`。那时开发者有一个使用 C 编写的 `lxc` 工具，在 `runc` 开发后，他们很快转向 `runc`。我很确信，当决定构建 libcontainer 时，他们对 `systemd-nspawn` 或其它非原生（即不使用 golang）的运行 namespaces 隔离的容器的方式都不感兴趣。
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://opensource.com/article/18/1/history-low-level-container-runtimes
|
||||
|
||||
作者：[Daniel Walsh][a]
|
||||
译者：[pinewall](https://github.com/pinewall)
|
||||
校对：[wxy](https://github.com/wxy)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]:https://opensource.com/users/rhatdan
|
||||
[1]:https://github.com/docker
|
||||
[2]:https://github.com/kubernetes-incubator/cri-o
|
||||
[3]:https://github.com/rkt/rkt
|
||||
[4]:https://github.com/projectatomic/libpod/tree/master/cmd/podman
|
||||
[5]:https://github.com/projectatomic/buildah
|
||||
[6]:https://libvirt.org/
|
||||
[7]:https://www.opencontainers.org/
|
||||
[8]:https://www.hyper.sh/
|
||||
[9]:https://github.com/opencontainers/runtime-spec
|
||||
[10]:https://github.com/opencontainers/runc
|
||||
[11]:https://github.com/cloudfoundry/garden
|
||||
[12]:https://clearlinux.org/containers
|
||||
[13]:https://github.com/oracle/railcar
|
||||
[14]:https://github.com/vbatts/nspawn-oci
|
||||
[15]:https://github.com/kata-containers
|
||||
@ -5,27 +5,22 @@
|
||||
|
||||
下面我将为你展示，如何在 [Go][6] 中实现一个 HTTP API 去提供这种服务。
|
||||
|
||||
### 业务流
|
||||
### 流程
|
||||
|
||||
* 用户输入他的电子邮件地址。
|
||||
|
||||
* 服务器创建一个临时的一次性使用的代码（就像一个临时密码一样）关联到用户，然后给用户邮箱中发送一个“魔法链接”。
|
||||
|
||||
* 用户点击魔法链接。
|
||||
|
||||
* 服务器提取魔法链接中的代码，获取关联的用户，并且使用一个新的 JWT 重定向到客户端。
|
||||
|
||||
* 在每次有新请求时，客户端使用 JWT 去验证用户。
|
||||
|
||||
### 必需条件
|
||||
|
||||
* 数据库：我们为这个服务使用了一个叫 [CockroachDB][1] 的 SQL 数据库。它非常像 postgres，但它是用 Go 写的。
|
||||
* SMTP 服务器：我们将使用一个第三方的邮件服务器去发送邮件。开发的时我们使用 [mailtrap][2]。Mailtrap 发送所有的邮件到它的收件箱，因此，你在测试时不需要创建多个假邮件帐户。
|
||||
|
||||
* SMTP 服务器：我们将使用一个第三方的邮件服务器去发送邮件。开发的时我们使用 [mailtrap][2]。Mailtrap 发送所有的邮件到它的收件箱，因此，你在测试它们时不需要创建多个假冒邮件帐户。
|
||||
从 [Go 的主页][7] 上安装它，然后使用 `go version`（1.10.1 atm）命令去检查它能否正常工作。
|
||||
|
||||
从 [它的主页][7] 上安装 Go，然后使用 `go version`（1.10.1 atm）命令去检查它能否正常工作。
|
||||
|
||||
从 [它的主页][8] 上下载 CockroachDB，展开它并添加到你的 `PATH` 变量中。使用 `cockroach version`（2.0 atm）命令检查它能否正常工作。
|
||||
从 [CockroachDB 的主页][8] 上下载它，展开它并添加到你的 `PATH` 变量中。使用 `cockroach version`（2.0 atm）命令检查它能否正常工作。
|
||||
|
||||
### 数据库模式
|
||||
|
||||
@ -33,7 +28,6 @@
|
||||
|
||||
```
|
||||
cockroach start --insecure --host 127.0.0.1
|
||||
|
||||
```
|
||||
|
||||
它会输出一些内容，找到 SQL 地址行，它将显示像 `postgresql://root@127.0.0.1:26257?sslmode=disable` 这样的内容。稍后我们将使用它去连接到数据库。
|
||||
@ -62,7 +56,7 @@ INSERT INTO users (email, username) VALUES
|
||||
|
||||
```
|
||||
|
||||
这个脚本创建了一个名为 `passwordless_demo` 的数据库、两个名为 `users` 和 `verification_codes` 的表，以及为了稍后测试而插入的一些假冒用户。每个验证代码都与用户关联并保存代码创建数据，以用于去检查代码是否过期。
|
||||
这个脚本创建了一个名为 `passwordless_demo` 的数据库、两个名为 `users` 和 `verification_codes` 的表，以及为了稍后测试而插入的一些假用户。每个验证代码都与用户关联并保存创建时间，以用于去检查验证代码是否过期。
|
||||
|
||||
在另外的终端中使用 `cockroach sql` 命令去运行这个脚本：
|
||||
|
||||
@ -80,9 +74,7 @@ cat schema.sql | cockroach sql --insecure
|
||||
我们需要下列的 Go 包：
|
||||
|
||||
* [github.com/lib/pq][3]：它是 CockroachDB 使用的 postgres 驱动
|
||||
|
||||
* [github.com/matryer/way][4]: 路由器
|
||||
|
||||
* [github.com/dgrijalva/jwt-go][5]: JWT 实现
|
||||
|
||||
```
|
||||
@ -94,7 +86,7 @@ go get -u github.com/dgrijalva/jwt-go
|
||||
|
||||
### 代码
|
||||
|
||||
### 初始化函数
|
||||
#### 初始化函数
|
||||
|
||||
创建 `main.go` 并且通过 `init` 函数里的环境变量中取得一些配置来启动。
|
||||
|
||||
@ -137,22 +129,16 @@ func env(key, fallbackValue string) string {
|
||||
```
|
||||
|
||||
* `appURL` 将去构建我们的 “魔法链接”。
|
||||
|
||||
* `port` 将要启动的 HTTP 服务器。
|
||||
|
||||
* `databaseURL` 是 CockroachDB 地址，我添加 `/passwordless_demo` 前面的数据库地址去表示数据库名字。
|
||||
|
||||
* `jwtKey` 用于签名 JWTs。
|
||||
|
||||
* `jwtKey` 用于签名 JWT。
|
||||
* `smtpAddr` 是 `SMTP_HOST` + `SMTP_PORT` 的联合；我们将使用它去发送邮件。
|
||||
|
||||
* `smtpUsername` 和 `smtpPassword` 是两个必需的变量。
|
||||
|
||||
* `smtpAuth` 也是用于发送邮件。
|
||||
|
||||
`env` 函数允许我们去获得环境变量，不存在时返回一个 fallback value。
|
||||
`env` 函数允许我们去获得环境变量，不存在时返回一个回退值。
|
||||
|
||||
### 主函数
|
||||
#### 主函数
|
||||
|
||||
```
|
||||
var db *sql.DB
|
||||
@ -174,7 +160,7 @@ func main() {
|
||||
router.Handle("GET", "/api/auth_user", authRequired(getAuthUser))
|
||||
|
||||
addr := fmt.Sprintf(":%d", config.port)
|
||||
log.Printf("starting server at %s 🚀\n", config.appURL)
|
||||
log.Printf("starting server at %s \n", config.appURL)
|
||||
log.Fatalf("could not start server: %v\n", http.ListenAndServe(addr, router))
|
||||
}
|
||||
|
||||
@ -189,7 +175,7 @@ import (
|
||||
|
||||
```
|
||||
|
||||
然后，我们创建路由器并定义一些端点。对于无密码业务流来说，我们使用两个端点：`/api/passwordless/start` 发送魔法链接，和 `/api/passwordless/verify_redirect` 用 JWT 响应。
|
||||
然后，我们创建路由器并定义一些端点。对于无密码流程来说，我们使用两个端点：`/api/passwordless/start` 发送魔法链接，和 `/api/passwordless/verify_redirect` 用 JWT 响应。
|
||||
|
||||
最后，我们启动服务器。
|
||||
|
||||
@ -234,9 +220,9 @@ go build
|
||||
|
||||
```
|
||||
|
||||
我们在目录中有了一个 “passwordless-demo”，但是你的目录中可能与示例不一样，`go build` 将创建一个同名的可执行文件。如果你没有关闭前面的 cockroach 节点，并且你正确配置了 `SMTP_USERNAME` 和 `SMTP_PASSWORD` 变量，你将看到命令 `starting server at http://localhost/ 🚀` 没有错误输出。
|
||||
我们在目录中有了一个 “passwordless-demo”，但是你的目录中可能与示例不一样，`go build` 将创建一个同名的可执行文件。如果你没有关闭前面的 cockroach 节点，并且你正确配置了 `SMTP_USERNAME` 和 `SMTP_PASSWORD` 变量，你将看到命令 `starting server at http://localhost/ ` 没有错误输出。
|
||||
|
||||
### JSON 要求的中间件
|
||||
#### 请求 JSON 的中间件
|
||||
|
||||
端点需要从请求体中解码 JSON，因此要确保请求是 `application/json` 类型。因为它是一个通用的东西，我将它解耦到中间件。
|
||||
|
||||
@ -257,7 +243,7 @@ func jsonRequired(next http.HandlerFunc) http.HandlerFunc {
|
||||
|
||||
实现很容易。首先它从请求头中获得内容的类型，然后检查它是否是以 “application/json” 开始，如果不是则以 `415 Unsupported Media Type` 提前返回。
|
||||
|
||||
### 响应 JSON 函数
|
||||
#### 响应 JSON 的函数
|
||||
|
||||
以 JSON 响应是非常通用的做法，因此我把它提取到函数中。
|
||||
|
||||
@ -285,7 +271,7 @@ func respondJSON(w http.ResponseWriter, payload interface{}, code int) {
|
||||
|
||||
首先，对原始类型做一个类型判断，并将它们封装到一个 `map`。然后将它们编组到 JSON，设置响应内容类型和状态码，并写 JSON。如果 JSON 编组失败，则响应一个内部错误。
|
||||
|
||||
### 响应内部错误的函数
|
||||
#### 响应内部错误的函数
|
||||
|
||||
`respondInternalError` 是一个响应 `500 Internal Server Error` 的函数，但是也同时将错误输出到控制台。
|
||||
|
||||
@ -299,7 +285,7 @@ func respondInternalError(w http.ResponseWriter, err error) {
|
||||
|
||||
```
|
||||
|
||||
### 创建用户处理程序
|
||||
#### 创建用户的处理程序
|
||||
|
||||
下面开始编写 `createUser` 处理程序，因为它非常容易并且是 REST 式的。
|
||||
|
||||
@ -391,7 +377,7 @@ respondJSON(w, user, http.StatusCreated)
|
||||
|
||||
最后使用创建的用户去响应。
|
||||
|
||||
### 无密码验证开始部分的处理程序
|
||||
#### 无密码验证开始部分的处理程序
|
||||
|
||||
```
|
||||
type PasswordlessStartRequest struct {
|
||||
@ -401,7 +387,7 @@ type PasswordlessStartRequest struct {
|
||||
|
||||
```
|
||||
|
||||
这个结构体持有 `passwordlessStart` 的请求体。希望去登入的用户 email。来自客户端的重定向 URI（这个应用中将使用我们的 API）如：`https://frontend.app/callback`。
|
||||
这个结构体含有 `passwordlessStart` 的请求体：希望去登入的用户 email、来自客户端的重定向 URI（这个应用中将使用我们的 API）如：`https://frontend.app/callback`。
|
||||
|
||||
```
|
||||
var magicLinkTmpl = template.Must(template.ParseFiles("templates/magic-link.html"))
|
||||
@ -429,7 +415,7 @@ var magicLinkTmpl = template.Must(template.ParseFiles("templates/magic-link.html
|
||||
|
||||
这个模板是给用户发送魔法链接邮件用的。你可以根据你的需要去随意调整它。
|
||||
|
||||
现在， 进入 `passwordlessStart` 函数**内部**：
|
||||
现在， 进入 `passwordlessStart` 函数内部：
|
||||
|
||||
```
|
||||
var input PasswordlessStartRequest
|
||||
@ -525,7 +511,7 @@ w.WriteHeader(http.StatusNoContent)
|
||||
|
||||
最后，设置响应状态码为 `204 No Content`。对于成功的状态码，客户端不需要很多数据。
|
||||
|
||||
### 发送邮件函数
|
||||
#### 发送邮件函数
|
||||
|
||||
```
|
||||
func sendMail(to mail.Address, subject, body string) error {
|
||||
@ -558,16 +544,16 @@ func sendMail(to mail.Address, subject, body string) error {
|
||||
|
||||
这个函数创建一个基本的 HTML 邮件结构体并使用 SMTP 服务器去发送它。邮件的内容你可以随意定制，我喜欢使用比较简单的内容。
|
||||
|
||||
### 无密码验证重定向处理程序
|
||||
#### 无密码验证重定向的处理程序
|
||||
|
||||
```
|
||||
var rxUUID = regexp.MustCompile("^[0-9a-f]{8}-[0-9a-f]{4}-4[0-9a-f]{3}-[89ab][0-9a-f]{3}-[0-9a-f]{12}$")
|
||||
|
||||
```
|
||||
|
||||
首先，这个正则表达式去验证一个 UUID（验证代码）。
|
||||
首先，这个正则表达式去验证一个 UUID（即验证代码）。
|
||||
|
||||
现在进入 `passwordlessVerifyRedirect` 函数 **内部**：
|
||||
现在进入 `passwordlessVerifyRedirect` 函数内部：
|
||||
|
||||
```
|
||||
q := r.URL.Query()
|
||||
@ -661,23 +647,19 @@ http.Redirect(w, r, callback.String(), http.StatusFound)
|
||||
|
||||
* * *
|
||||
|
||||
无密码的工作流已经完成。现在需要去写 `getAuthUser` 端点的代码了，它用于获取当前验证用户的信息。你应该还记得，这个端点使用了 `authRequired` 中间件。
|
||||
无密码的流程已经完成。现在需要去写 `getAuthUser` 端点的代码了，它用于获取当前验证用户的信息。你应该还记得，这个端点使用了 `guard` 中间件。
|
||||
|
||||
### 使用 Auth 中间件
|
||||
#### 使用 Auth 中间件
|
||||
|
||||
在编写 `authRequired` 中间件之前，我将编写一个不需要验证的分支。目的是，如果没有传递 JWT，它将不去验证用户。
|
||||
在编写 `guard` 中间件之前，我将编写一个不需要验证的分支。目的是，如果没有传递 JWT，它将不去验证用户。
|
||||
|
||||
```
|
||||
type ContextKey int
|
||||
|
||||
const (
|
||||
keyAuthUserID ContextKey = iota
|
||||
)
|
||||
|
||||
func jwtKeyFunc(*jwt.Token) (interface{}, error) {
|
||||
return config.jwtKey, nil
|
||||
type ContextKey struct {
|
||||
Name string
|
||||
}
|
||||
|
||||
var keyAuthUserID = ContextKey{"auth_user_id"}
|
||||
|
||||
func withAuth(next http.HandlerFunc) http.HandlerFunc {
|
||||
return func(w http.ResponseWriter, r *http.Request) {
|
||||
a := r.Header.Get("Authorization")
|
||||
@ -689,7 +671,11 @@ func withAuth(next http.HandlerFunc) http.HandlerFunc {
|
||||
tokenString := a[7:]
|
||||
|
||||
p := jwt.Parser{ValidMethods: []string{jwt.SigningMethodHS256.Name}}
|
||||
token, err := p.ParseWithClaims(tokenString, &jwt.StandardClaims{}, jwtKeyFunc)
|
||||
token, err := p.ParseWithClaims(
|
||||
tokenString,
|
||||
&jwt.StandardClaims{},
|
||||
func (*jwt.Token) (interface{}, error) { return config.jwtKey, nil },
|
||||
)
|
||||
if err != nil {
|
||||
respondJSON(w, http.StatusText(http.StatusUnauthorized), http.StatusUnauthorized)
|
||||
return
|
||||
@ -707,19 +693,18 @@ func withAuth(next http.HandlerFunc) http.HandlerFunc {
|
||||
next(w, r.WithContext(ctx))
|
||||
}
|
||||
}
|
||||
|
||||
```
|
||||
|
||||
JWT 将在每次请求时以 “Bearer <token_here>” 格式包含在 “Authorization” 头中。因此，如果没有提供令牌，我们将直接通过，进入接下来的中间件。
|
||||
JWT 将在每次请求时以 `Bearer <token_here>` 格式包含在 `Authorization` 头中。因此，如果没有提供令牌，我们将直接通过，进入接下来的中间件。
|
||||
|
||||
我们创建一个解析器来解析令牌。如果解析失败则返回 `401 Unauthorized`。
|
||||
|
||||
然后我们从 JWT 中提取出要求的内容，并添加 `Subject`（就是用户 ID）到需要的地方。
|
||||
|
||||
### Auth 需要的中间件
|
||||
#### Guard 中间件
|
||||
|
||||
```
|
||||
func authRequired(next http.HandlerFunc) http.HandlerFunc {
|
||||
func guard(next http.HandlerFunc) http.HandlerFunc {
|
||||
return withAuth(func(w http.ResponseWriter, r *http.Request) {
|
||||
_, ok := r.Context().Value(keyAuthUserID).(string)
|
||||
if !ok {
|
||||
@ -729,15 +714,13 @@ func authRequired(next http.HandlerFunc) http.HandlerFunc {
|
||||
next(w, r)
|
||||
})
|
||||
}
|
||||
|
||||
|
||||
```
|
||||
|
||||
现在，`authRequired` 将使用 `withAuth` 并从请求内容中提取出验证用户的 ID。如果提取失败，它将返回 `401 Unauthorized`，提取成功则继续下一步。
|
||||
现在，`guard` 将使用 `withAuth` 并从请求内容中提取出验证用户的 ID。如果提取失败，它将返回 `401 Unauthorized`，提取成功则继续下一步。
|
||||
|
||||
### 获取 Auth 用户
|
||||
#### 获取 Auth 用户
|
||||
|
||||
在 `getAuthUser` 处理程序**内部**：
|
||||
在 `getAuthUser` 处理程序内部：
|
||||
|
||||
```
|
||||
ctx := r.Context()
|
||||
@ -756,9 +739,9 @@ respondJSON(w, user, http.StatusOK)
|
||||
|
||||
```
|
||||
|
||||
首先，我们从请求内容中提取验证用户的 ID，我们使用这个 ID 去获取用户。如果没有获取到内容，则发送一个 `418 I'm a teapot`，或者一个内部错误。最后，我们将用这个用户去响应 😊
|
||||
首先，我们从请求内容中提取验证用户的 ID，我们使用这个 ID 去获取用户。如果没有获取到内容，则发送一个 `418 I'm a teapot`，或者一个内部错误。最后，我们将用这个用户去响应。
|
||||
|
||||
### 获取 User 函数
|
||||
#### 获取 User 函数
|
||||
|
||||
下面你看到的是 `fetchUser` 函数。
|
||||
|
||||
@ -781,17 +764,17 @@ func fetchUser(ctx context.Context, id string) (User, error) {
|
||||
|
||||
如果你在 mailtrap 上点击之后出现有关 `脚本运行被拦截，因为文档的框架是沙箱化的，并且没有设置 'allow-scripts' 权限` 的问题，你可以尝试右键点击 “在新标签中打开链接“。这样做是安全的，因为邮件内容是 [沙箱化的][10]。我在 `localhost` 上有时也会出现这个问题，但是我认为你一旦以 `https://` 方式部署到服务器上应该不会出现这个问题了。
|
||||
|
||||
如果有任何问题，请在我的 [GitHub repo][11] 留言或者提交 PRs 👍
|
||||
如果有任何问题，请在我的 [GitHub repo][11] 留言或者提交 PRs
|
||||
|
||||
以后，我将为这个 API 写一个客户端作为这篇文章的第二部分。
|
||||
以后，我为这个 API 写了一个客户端作为这篇文章的[第二部分][13]。
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://nicolasparada.netlify.com/posts/passwordless-auth-server/
|
||||
|
||||
作者：[Nicolás Parada ][a]
|
||||
作者：[Nicolás Parada][a]
|
||||
译者：[qhwdw](https://github.com/qhwdw)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
校对：[wxy](https://github.com/wxy)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
@ -808,3 +791,4 @@ via: https://nicolasparada.netlify.com/posts/passwordless-auth-server/
|
||||
[10]:https://developer.mozilla.org/en-US/docs/Web/HTML/Element/iframe#attr-sandbox
|
||||
[11]:https://github.com/nicolasparada/go-passwordless-demo
|
||||
[12]:https://twitter.com/intent/retweet?tweet_id=986602458716803074
|
||||
[13]:https://nicolasparada.netlify.com/posts/passwordless-auth-client/
|
||||
@ -1,202 +0,0 @@
|
||||
How to Install Docker CE on Your Desktop
|
||||
======
|
||||
|
||||
|
||||
|
||||
[In the previous article,][1] we learned some of the basic terminologies of the container world. That background information will come in handy when we run commands and use some of those terms in follow-up articles, including this one. This article will cover the installation of Docker on desktop Linux, macOS, and Windows, and it is intended for beginners who want to get started with Docker containers. The only prerequisite is that you are comfortable with command-line interface.
|
||||
|
||||
### Why do I need Docker CE on my local machine?
|
||||
|
||||
As a new user, you many wonder why you need containers on your local systems. Aren’t they meant to run in cloud and servers as microservices? While containers have been part of the Linux world for a very long time, it was Docker that made them really consumable with its tools and technologies.
|
||||
|
||||
The greatest thing about Docker containers is that you can use your local machine for development and testing. The container images that you create on your local system can then run “anywhere.” There is no conflict between developers and operators about apps running fine on development systems but not in production.
|
||||
|
||||
The point is that in order to create containerized applications, you must be able to run and create containers on your local systems.
|
||||
|
||||
You can use any of the three platforms -- desktop Linux, Windows, or macOS as the development platform for containers. Once Docker is successfully running on these systems, you will be using the same commands across platforms so it really doesn’t matter which OS you are running underneath.
|
||||
|
||||
That’s the beauty of Docker.
|
||||
|
||||
### Let’s get started
|
||||
|
||||
There are two editions of Docker. Docker Enterprise Edition (EE) and Docker Community Edition (CE). We will be using the Docker Community Edition, which is a free of cost version of Docker intended for developers and enthusiasts who want to get started with Docker.
|
||||
|
||||
There are two channels of Docker CE: stable and edge. As the name implies, the stable version gives you well-tested quarterly updates, whereas the edge version offers new updates every month. After further testing, these edge features are added to the stable release. I recommend the stable version for new users.
|
||||
Docker CE is supported on macOS, Windows 10, Ubuntu 14.04, 16.04, 17.04 and 17.10; Debian 7.7,8,9 and 10; Fedora 25, 26, 27; and centOS. While you can download Docker CE binaries and install on your Desktop Linux systems, I recommend adding repositories so you continue to receive patches and updates.
|
||||
|
||||
### Install Docker CE on Desktop Linux
|
||||
|
||||
You don’t need a full blown desktop Linux to run Docker, you can install it on a bare minimal Linux server as well, that you can run in a VM. In this tutorial, I am running it on Fedora 27 and Ubuntu 17.04 running on my main systems.
|
||||
|
||||
### Ubuntu Installation
|
||||
|
||||
First things first. Run a system update so your Ubuntu packages are fully updated:
|
||||
```
|
||||
$ sudo apt-get update
|
||||
|
||||
```
|
||||
|
||||
Now run system upgrade:
|
||||
```
|
||||
$ sudo apt-get dist-upgrade
|
||||
|
||||
```
|
||||
|
||||
Then install Docker PGP keys:
|
||||
```
|
||||
sudo add-apt-repository "deb [arch=amd64] https://download.docker.com/linux/ubuntu $(lsb_release -cs) stable"
|
||||
|
||||
Update the repository info again:
|
||||
$ sudo apt-get update
|
||||
|
||||
```
|
||||
|
||||
Now install Docker CE:
|
||||
```
|
||||
$ sudo apt-get install docker-ce
|
||||
|
||||
```
|
||||
|
||||
Once it's installed, Docker CE runs automatically on Ubuntu based systems. Let’s check if it’s running:
|
||||
```
|
||||
$ sudo systemctl status docker
|
||||
|
||||
```
|
||||
|
||||
You should get the following output:
|
||||
```
|
||||
docker.service - Docker Application Container Engine
|
||||
Loaded: loaded (/lib/systemd/system/docker.service; enabled; vendor preset: enabled)
|
||||
Active: active (running) since Thu 2017-12-28 15:06:35 EST; 19min ago
|
||||
Docs: https://docs.docker.com
|
||||
Main PID: 30539 (dockerd)
|
||||
|
||||
```
|
||||
|
||||
Since Docker is installed on your system, you can now use Docker CLI (Command Line Interface) to run Docker commands. Living up to the tradition, let’s run the ‘Hello World’ command:
|
||||
```
|
||||
$ sudo docker run hello-world
|
||||
|
||||
```
|
||||
|
||||
![YMChR_7xglpYBT91rtXnqQc6R1Hx9qMX_iO99vL8][2]
|
||||
Congrats! You have Docker running on your Ubuntu system.
|
||||
|
||||
### Installing Docker CE on Fedora
|
||||
|
||||
Things are a bit different on Fedora 27. On Fedora, you first need to install def-plugins-core packages that will allow you to manage your DNF packages from CLI.
|
||||
```
|
||||
$ sudo dnf -y install dnf-plugins-core
|
||||
|
||||
```
|
||||
|
||||
Now install the Docker repo on your system:
|
||||
```
|
||||
$ sudo dnf config-manager \
|
||||
--add-repo \
|
||||
https://download.docker.com/linux/fedora/docker-ce.repo
|
||||
It’s time to install Docker CE:
|
||||
|
||||
$ sudo dnf install docker-ce
|
||||
|
||||
```
|
||||
|
||||
Unlike Ubuntu, Docker doesn’t start automatically on Fedora. So let’s start it:
|
||||
```
|
||||
$ sudo systemctl start docker
|
||||
|
||||
```
|
||||
|
||||
You will have to start Docker manually after each reboot, so let’s configure it to start automatically after reboots. $ systemctl enable docker Well, it’s time to run the Hello World command:
|
||||
```
|
||||
$ sudo docker run hello-world
|
||||
|
||||
```
|
||||
|
||||
Congrats, Docker is running on your Fedora 27 system.
|
||||
|
||||
### Cutting your roots
|
||||
|
||||
You may have noticed that you have to use sudo to run Docker commands. That’s because of Docker daemon’s binding with the UNIX socket, instead of a TCP port and that socket is owned by the root user. So, you need sudo privileges to run the docker command. You can add system user to the docker group so it won’t require sudo:
|
||||
```
|
||||
$ sudo groupadd docker
|
||||
|
||||
```
|
||||
|
||||
In most cases, the docker user group is automatically created when you install Docker CE, so all you need to do is add your user to that group:
|
||||
```
|
||||
$ sudo usermod -aG docker $USER
|
||||
|
||||
```
|
||||
|
||||
To test if the group has been added successfully, run the groups command against the name of the user:
|
||||
```
|
||||
$ groups swapnil
|
||||
|
||||
```
|
||||
|
||||
(Here, Swapnil is the user.)
|
||||
|
||||
This is the output on my system:
|
||||
```
|
||||
$ swapnil : swapnil adm cdrom sudo dip plugdev lpadmin sambashare docker
|
||||
|
||||
```
|
||||
|
||||
You can see that the user also belongs to the docker group. Log out of your system, so that group changes take effect. Once you log back in, try the Hello World command without sudo:
|
||||
```
|
||||
$ docker run hello-world
|
||||
|
||||
```
|
||||
|
||||
You can check system wide info about the installed version of Docker and more by running this command:
|
||||
```
|
||||
$ docker info
|
||||
|
||||
```
|
||||
|
||||
### Install Docker CE on macOS and Windows
|
||||
|
||||
You can easily install Docker CE (and EE) on macOS and Windows. Download the official Docker for Mac and install it the way you install applications on macOS, by simply dragging them into the Applications directory. Once the file is copied, open Docker from spotlight to start the installation process. Once installed, Docker will start automatically and you can see it in the top bar of macOS.
|
||||
|
||||
![IEX23j65zYlF8mZ1c-T_vFw_i1B1T1hibw_AuhEA][3]
|
||||
|
||||
macOS is UNIX, so you can simply open the terminal app and start using Docker commands natively. Test the hello world app:
|
||||
```
|
||||
$ docker run hello-world
|
||||
|
||||
```
|
||||
|
||||
Congrats, you have Docker running on your macOS.
|
||||
|
||||
### Docker on Windows 10
|
||||
|
||||
You need the latest version of Windows 10 Pro or Server in order to run/install Docker on it. If you are not fully updated, Windows won’t install Docker. I got an error on my Windows 10 system and had to run system updates. My version was still behind, and I hit [this][4] bug. So, if you fail to install Docker on Windows, just know you are not alone. Keep an eye on that bug to find a solution.
|
||||
|
||||
Once you install Docker on Windows, you can either use bash shell via WSL or use PowerShell to run docker commands. Let’s test the “Hello World” command in PowerShell:
|
||||
```
|
||||
PS C:\Users\swapnil> docker run hello-world
|
||||
|
||||
```
|
||||
|
||||
Congrats, you have Docker running on Windows.
|
||||
|
||||
In the next article, we will talk about pulling images from DockerHub and running containers on our systems. We will also talk about pushing our own containers to Docker Hub.
|
||||
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://www.linux.com/blog/learn/intro-to-linux/how-install-docker-ce-your-desktop
|
||||
|
||||
作者：[SWAPNIL BHARTIYA][a]
|
||||
译者：[译者ID](https://github.com/译者ID)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
选题：[lujun9972](https://github.com/lujun9972)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]:https://www.linux.com/users/arnieswap
|
||||
[1]:https://www.linux.com/blog/intro-to-linux/2017/12/container-basics-terms-you-need-know
|
||||
[2]:https://lh5.googleusercontent.com/YMChR_7xglpYBT91rtXnqQc6R1Hx9qMX_iO99vL8Z8C0-BlynDcL5B5pG-zzH0fKU0Qvnzd89v0KDEbZiO0gTfGNGfDtO-FkTt0bmzIQ-TKbNmv18S9RXdkSeXqgKDFRewnaHPj2
|
||||
[3]:https://lh3.googleusercontent.com/IEX23j65zYlF8mZ1c-T_vFw_i1B1T1hibw_AuhEAfwv9oFpMfcAqkgEk7K5o58iDAAfGozSpIvY_qEsTOHRlSbesMKwTnG9rRkWba1KPSmnuH1LyoccDGNO3Clbz8du0gSByZxNj
|
||||
[4]:https://github.com/docker/for-win/issues/1263
|
||||
@ -1,3 +1,5 @@
|
||||
translating---geekpi
|
||||
|
||||
How To Run A Command For A Specific Time In Linux
|
||||
======
|
||||
|
||||
|
||||
@ -1,245 +0,0 @@
|
||||
The Linux Filesystem Explained
|
||||
======
|
||||
|
||||
|
||||
Back in 1996 I learned how to install software on my spanking new Linux before really understanding the topography of the filesystem. This turned out to be a problem, not so much for programs, because they would just magically work even though I hadn't a clue of where the actual executable files landed. The problem was the documentation.
|
||||
|
||||
You see, back then, Linux was not the intuitive, user-friendly system it is today. You had to read a lot. You had to know things about the frequency rate of your CRT monitor and the ins and outs of your noisy dial-up modem, among hundreds of other things. I soon realized I would need to spend some time getting a handle on how the directories were organized and what all their exotic names like /etc (not for miscellaneous files), /usr (not for user files), and /*bin *(not a trash can) meant.
|
||||
|
||||
This tutorial will help you get up to speed faster than I did.
|
||||
|
||||
### Structure
|
||||
|
||||
It makes sense to explore the Linux filesystem from a terminal window, not because the author is a grumpy old man and resents new kids and their pretty graphical tools -- although there is some truth to that -- but because a terminal, despite being text-only, has better tools to show the map of Linux's directory tree.
|
||||
|
||||
In fact, that is the name of the first tool you'll install to help you on the way: _tree_. If you are using Ubuntu or Debian, you can do:
|
||||
```
|
||||
sudo apt install tree
|
||||
|
||||
```
|
||||
|
||||
On Red Hat or Fedora, do:
|
||||
```
|
||||
sudo dnf install tree
|
||||
|
||||
```
|
||||
|
||||
For SUSE/openSUSE use `zypper`:
|
||||
```
|
||||
sudo zypper install tree
|
||||
|
||||
```
|
||||
|
||||
For Arch-like distros (Manjaro, Antergos, etc.) use:
|
||||
```
|
||||
sudo pacman -S tree
|
||||
|
||||
```
|
||||
|
||||
... and so on.
|
||||
|
||||
Once installed, stay in your terminal window and run _tree_ like this:
|
||||
```
|
||||
tree /
|
||||
|
||||
```
|
||||
|
||||
`The /` in the instruction above refers to the _root_ directory. The root directory is the one from which all other directories branch off from. When you run `tree` and tell it to start with _/_ , you will see the whole directory tree, all directories and all the subdirectories in the whole system, with all their files, fly by.
|
||||
|
||||
If you have been using your system for some time, this may take a while, because, even if you haven't generated many files yourself, a Linux system and its apps are always logging, cacheing, and storing temporal files. The number of entries in the file system can grow quite quickly.
|
||||
|
||||
Don't feel overwhelmed, though. Instead, try this:
|
||||
```
|
||||
tree -L 1 /
|
||||
|
||||
```
|
||||
|
||||
And you should see what is shown in Figure 1.
|
||||
|
||||
|
||||
|
||||
The instruction above can be translated as " _show me only the 1st Level of the directory tree starting at / (root)_ ". The `-L` option tells `tree` how many levels down you want to see.
|
||||
|
||||
Most Linux distributions will show you the same or a very similar layout to what you can see in the image above. This means that even if you feel confused now, master this, and you will have a handle on most, if not all, Linux installations in the whole wide world.
|
||||
|
||||
To get you started on the road to mastery, let's look at what each directory is used for. While we go through each, you can peek at their contents using ls.
|
||||
|
||||
### Directories
|
||||
|
||||
From top to bottom, the directories you are seeing are as follows.
|
||||
|
||||
#### _/bin_
|
||||
|
||||
_/bin_ is the directory that contains _bin_ aries, that is, some of the applications and programs you can run. You will find the _ls_ program mentioned above in this directory, as well as other basic tools for making and removing files and directories, moving them around, and so on. There are more _bin_ directories in other parts of the file system tree, but we'll be talking about those in a minute.
|
||||
|
||||
#### _/boot_
|
||||
|
||||
The _/boot_ directory contains files required for starting your system. Do I have to say this? Okay, I'll say it: **DO NOT TOUCH!**. If you mess up one of the files in here, you may not be able to run your Linux and it is a pain to repair. On the other hand, don't worry too much about destroying your system by accident: you have to have superuser privileges to do that.
|
||||
|
||||
#### _/dev_
|
||||
|
||||
_/dev_ contains _dev_ ice files. Many of these are generated at boot time or even on the fly. For example, if you plug in a new webcam or a USB pendrive into your machine, a new device entry will automagically pop up here.
|
||||
|
||||
#### _/etc_
|
||||
|
||||
_/etc_ is the directory where names start to get confusing. _/etc_ gets its name from the earliest Unixes and it was literally "et cetera" because it was the dumping ground for system files administrators were not sure where else to put.
|
||||
|
||||
Nowadays, it would be more appropriate to say that _etc_ stands for "Everything to configure," as it contains most, if not all system-wide configuration files. For example, the files that contain the name of your system, the users and their passwords, the names of machines on your network and when and where the partitions on your hard disks should be mounted are all in here. Again, if you are new to Linux, it may be best if you don't touch too much in here until you have a better understanding of how things work.
|
||||
|
||||
#### _/home_
|
||||
|
||||
_/home_ is where you will find your users' personal directories. In my case, under _/home_ there are two directories: _/home/paul_ , which contains all my stuff; and _/home/guest_ , in case anybody needs to borrow my computer.
|
||||
|
||||
#### _/lib_
|
||||
|
||||
_/lib_ is where _lib_ raries live. Libraries are files containing code that your applications can use. They contain snippets of code that applications use to draw windows on your desktop, control peripherals, or send files to your hard disk.
|
||||
|
||||
There are more _lib_ directories scattered around the file system, but this one, the one hanging directly off of _/_ is special in that, among other things, it contains the all-important kernel modules. The kernel modules are drivers that make things like your video card, sound card, WiFi, printer, and so on, work.
|
||||
|
||||
#### _/media_
|
||||
|
||||
The _/media_ directory is where external storage will be automatically mounted when you plug it in and try to access it. As opposed to most of the other items on this list, _/media_ does not hail back to 1970s, mainly because inserting and detecting storage (pendrives, USB hard disks, SD cards, external SSDs, etc) on the fly, while a computer is running, is a relatively new thing.
|
||||
|
||||
#### _/mnt_
|
||||
|
||||
The _/mnt_ directory, however, is a bit of remnant from days gone by. This is where you would manually mount storage devices or partitions. It is not used very often nowadays.
|
||||
|
||||
#### _/opt_
|
||||
|
||||
The _/opt_ directory is often where software you compile (that is, you build yourself from source code and do not install from your distribution repositories) sometimes lands. Applications will end up in the _/opt/bin_ directory and libraries in the _/opt/lib_ directory.
|
||||
|
||||
A slight digression: another place where applications and libraries end up in is _/usr/local_ , When software gets installed here, there will also be _/usr/local/bin_ and _/usr/local/lib_ directories. What determines which software goes where is how the developers have configured the files that control the compilation and installation process.
|
||||
|
||||
#### _/proc_
|
||||
|
||||
_/proc_ , like _/dev_ is a virtual directory. It contains information about your computer, such as information about your CPU and the kernel your Linux system is running. As with _/dev_ , the files and directories are generated when your computer starts, or on the fly, as your system is running and things change.
|
||||
|
||||
#### _/root_
|
||||
|
||||
_/root_ is the home directory of the superuser (also known as the "Administrator") of the system. It is separate from the rest of the users' home directories BECAUSE YOU ARE NOT MEANT TO TOUCH IT. Keep your own stuff in you own directories, people.
|
||||
|
||||
#### _/run_
|
||||
|
||||
_/run_ is another new directory. System processes use it to store temporary data for their own nefarious reasons. This is another one of those DO NOT TOUCH folders.
|
||||
|
||||
#### _/sbin_
|
||||
|
||||
_/sbin_ is similar to _/bin_ , but it contains applications that only the superuser (hence the initial _s_ ) will need. You can use these applications with the `sudo` command that temporarily concedes you superuser powers on many distributions. _/sbin_ typically contains tools that can install stuff, delete stuff and format stuff. As you can imagine, some of these instructions are lethal if you use them improperly, so handle with care.
|
||||
|
||||
#### _/usr_
|
||||
|
||||
The _/usr_ directory was where users' home directories were originally kept back in the early days of UNIX. However, now _/home_ is where users kept their stuff as we saw above. These days, _/usr_ contains a mish-mash of directories which in turn contain applications, libraries, documentation, wallpapers, icons and a long list of other stuff that need to be shared by applications and services.
|
||||
|
||||
You will also find _bin_ , _sbin_ and _lib_ directories in _/usr_. What is the difference with their root-hanging cousins? Not much nowadays. Originally, the _/bin_ directory (hanging off of root) would contain very basic commands, like `ls`, `mv` and `rm`; the kind of commands that would come pre-installed in all UNIX/Linux installations, the bare minimum to run and maintain a system. _/usr/bin_ on the other hand would contain stuff the users would install and run to use the system as a work station, things like word processors, web browsers, and other apps.
|
||||
|
||||
But many modern Linux distributions just put everything into _/usr/bin_ and have _/bin_ point to _/usr/bin_ just in case erasing it completely would break something. So, while Debian, Ubuntu and Mint still keep _/bin_ and _/usr/bin_ (and _/sbin_ and _/usr/sbin_ ) separate; others, like Arch and its derivatives just have one "real" directory for binaries, _/usr/bin_ , and the rest or _*bin_ s are "fake" directories that point to _/usr/bin_.
|
||||
|
||||
#### _/srv_
|
||||
|
||||
The _/srv_ directory contains data for servers. If you are running a web server from your Linux box, your HTML files for your sites would go into _/srv/http_ (or _/srv/www_ ). If you were running an FTP server, your files would go into _/srv/ftp_.
|
||||
|
||||
#### _/sys_
|
||||
|
||||
_/sys_ is another virtual directory like _/proc_ and _/dev_ and also contains information from devices connected to your computer.
|
||||
|
||||
In some cases you can also manipulate those devices. I can, for example, change the brightness of the screen of my laptop by modifying the value stored in the _/sys/devices/pci0000:00/0000:00:02.0/drm/card1/card1-eDP-1/intel_backlight/brightness_ file (on your machine you will probably have a different file). But to do that you have to become superuser. The reason for that is, as with so many other virtual directories, messing with the contents and files in _/sys_ can be dangerous and you can trash your system. DO NOT TOUCH until you are sure you know what you are doing.
|
||||
|
||||
#### _/tmp_
|
||||
|
||||
_/tmp_ contains temporary files, usually placed there by applications that you are running. The files and directories often (not always) contain data that an application doesn't need right now, but may need later on. So, to free up RAM, it gets stored here.
|
||||
|
||||
You can also use _/tmp_ to store your own temporary files -- _/tmp_ is one of the few directories hanging of _/_ which you can actually interact with without becoming superuser. The problem is that applications sometimes don't come back to retrieve and delete files and directories and _/tmp_ can often end up eating up space on your hard disk, filling it up with junk. Later on in this series we'll see how to clean it up.
|
||||
|
||||
#### _/var_
|
||||
|
||||
_/var_ was originally given its name because its contents was deemed _variable_ , in that it changed frequently. Today it is a bit of a misnomer because there are many other directories that also contain data that changes frequently, especially the virtual directories we saw above.
|
||||
|
||||
Be that as it may, _/var_ contains things like logs in the _/var/log_ subdirectories. Logs are files that register events that happen on the system. If something fails in the kernel, it will be logged in a file in _/var/log_ ; if someone tries to break into your computer from outside, your firewall will also log the attempt here. It also contains _spools_ for tasks. These "tasks" can be the jobs you send to a shared printer when you have to wait because another user is printing a long document, or mail that is waiting to be delivered to users on the system.
|
||||
|
||||
Your system may have some more directories we haven't mentioned above. In the screenshot, for example, there is a _/snap_ directory. That's because the shot was captured on an Ubuntu system. Ubuntu has recently incorporated [snap][1] packages as a way of distributing software. The _/snap_ directory contains all the files and the software installed from snaps.
|
||||
|
||||
### Digging Deeper
|
||||
|
||||
That is the root directory covered, but many of the subdirectories lead to their own set of files and subdirectories. Figure 2 gives you an overall idea of what the basic file system tree looks like (the image is kindly supplied under a CC By-SA license by Paul Gardner) and [Wikipedia has a break down with a summary of what each directory is used for][2].
|
||||
|
||||
|
||||
![filesystem][4]
|
||||
|
||||
Figure 2: Standard Unix filesystem hierarchy.
|
||||
|
||||
[Used with permission][5]
|
||||
|
||||
Paul Gardner
|
||||
|
||||
To explore the filesystem yourself, use the `cd` command:
|
||||
```
|
||||
cd
|
||||
|
||||
```
|
||||
|
||||
will take you to the directory of your choice ( _cd_ stands for _change directory_.
|
||||
|
||||
If you get confused,
|
||||
```
|
||||
pwd
|
||||
|
||||
```
|
||||
|
||||
will always tell you where you ( _pwd_ stands for _print working directory_ ). Also,
|
||||
```
|
||||
cd
|
||||
|
||||
```
|
||||
|
||||
with no options or parameters, will take you back to your own home directory, where things are safe and cosy.
|
||||
|
||||
Finally,
|
||||
```
|
||||
cd ..
|
||||
|
||||
```
|
||||
|
||||
will take you up one level, getting you one level closer to the _/_ root directory. If you are in _/usr/share/wallpapers_ and run `cd ..`, you will move up to _/usr/share_.
|
||||
|
||||
To see what a directory contains, use
|
||||
```
|
||||
ls
|
||||
|
||||
```
|
||||
|
||||
or simply
|
||||
```
|
||||
ls
|
||||
|
||||
```
|
||||
|
||||
to list the contents of the directory you are in right now.
|
||||
|
||||
And, of course, you always have `tree` to get an overview of what lays within a directory. Try it on _/usr/share_ \-- there is a lot of interesting stuff in there.
|
||||
|
||||
### Conclusion
|
||||
|
||||
Although there are minor differences between Linux distributions, the layout for their filesystems are mercifully similar. So much so that you could say: once you know one, you know them all. And the best way to know the filesystem is to explore it. So go forth with `tree`, `ls`, and `cd` into uncharted territory.
|
||||
|
||||
You cannot damage your filesystem just by looking at it, so move from one directory to another and take a look around. Soon you'll discover that the Linux filesystem and how it is laid out really makes a lot of sense, and you will intuitively know where to find apps, documentation, and other resources.
|
||||
|
||||
Learn more about Linux through the free ["Introduction to Linux" ][6]course from The Linux Foundation and edX.
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://www.linux.com/blog/learn/intro-to-linux/2018/4/linux-filesystem-explained
|
||||
|
||||
作者：[PAUL BROWN][a]
|
||||
选题：[lujun9972](https://github.com/lujun9972)
|
||||
译者：[译者ID](https://github.com/译者ID)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]:https://www.linux.com/users/bro66
|
||||
[1]:https://www.ubuntu.com/desktop/snappy
|
||||
[2]:https://en.wikipedia.org/wiki/Unix_filesystem#Conventional_directory_layout
|
||||
[3]:https://www.linux.com/files/images/standard-unix-filesystem-hierarchypng
|
||||
[4]:https://www.linux.com/sites/lcom/files/styles/rendered_file/public/standard-unix-filesystem-hierarchy.png?itok=CVqmyk6P (filesystem)
|
||||
[5]:https://www.linux.com/licenses/category/used-permission
|
||||
[6]:https://training.linuxfoundation.org/linux-courses/system-administration-training/introduction-to-linux
|
||||
338
sources/tech/20180429 Passwordless Auth- Client.md
Normal file
338
sources/tech/20180429 Passwordless Auth- Client.md
Normal file
@ -0,0 +1,338 @@
|
||||
Passwordless Auth: Client
|
||||
======
|
||||
Time to continue with the [passwordless auth][1] posts. Previously, we wrote an HTTP service in Go that provided with a passwordless authentication API. Now, we are gonna code a JavaScript client for it.
|
||||
|
||||
We’ll go with a single page application (SPA) using the technique I showed [here][2]. Read it first if you haven’t yet.
|
||||
|
||||
For the root URL (`/`) we’ll show two different pages depending on the auth state: a page with an access form or a page greeting the authenticated user. Another page is for the auth callback redirect.
|
||||
|
||||
### Serving
|
||||
|
||||
I’ll serve the client with the same Go server, so let’s add some routes to the previous `main.go`:
|
||||
```
|
||||
router.Handle("GET", "/js/", http.FileServer(http.Dir("static")))
|
||||
router.HandleFunc("GET", "/...", serveFile("static/index.html"))
|
||||
|
||||
```
|
||||
|
||||
This serves files under `static/js`, and `static/index.html` is served for everything else.
|
||||
|
||||
You can use your own server apart, but you’ll have to enable [CORS][3] on the server.
|
||||
|
||||
### HTML
|
||||
|
||||
Let’s see that `static/index.html`.
|
||||
```
|
||||
<!DOCTYPE html>
|
||||
<html lang="en">
|
||||
<head>
|
||||
<meta charset="utf-8">
|
||||
<meta name="viewport" content="width=device-width, initial-scale=1.0">
|
||||
<title>Passwordless Demo</title>
|
||||
<link rel="shortcut icon" href="data:,">
|
||||
<script src="/js/main.js" type="module"></script>
|
||||
</head>
|
||||
<body></body>
|
||||
</html>
|
||||
|
||||
```
|
||||
|
||||
Single page application left all the rendering to JavaScript, so we have an empty body and a `main.js` file.
|
||||
|
||||
I’ll user the Router from the [last post][2].
|
||||
|
||||
### Rendering
|
||||
|
||||
Now, create a `static/js/main.js` file with the following content:
|
||||
```
|
||||
import Router from 'https://unpkg.com/@nicolasparada/router'
|
||||
import { isAuthenticated } from './auth.js'
|
||||
|
||||
const router = new Router()
|
||||
|
||||
router.handle('/', guard(view('home')))
|
||||
router.handle('/callback', view('callback'))
|
||||
router.handle(/^\//, view('not-found'))
|
||||
|
||||
router.install(async resultPromise => {
|
||||
document.body.innerHTML = ''
|
||||
document.body.appendChild(await resultPromise)
|
||||
})
|
||||
|
||||
function view(name) {
|
||||
return (...args) => import(`/js/pages/${name}-page.js`)
|
||||
.then(m => m.default(...args))
|
||||
}
|
||||
|
||||
function guard(fn1, fn2 = view('welcome')) {
|
||||
return (...args) => isAuthenticated()
|
||||
? fn1(...args)
|
||||
: fn2(...args)
|
||||
}
|
||||
|
||||
```
|
||||
|
||||
Differing from the last post, we implement an `isAuthenticated()` function and a `guard()` function that uses it to render one or another page. So when a user visits `/` it will show the home or welcome page whether the user is authenticated or not.
|
||||
|
||||
### Auth
|
||||
|
||||
Now, let’s write that `isAuthenticated()` function. Create a `static/js/auth.js` file with the following content:
|
||||
```
|
||||
export function getAuthUser() {
|
||||
const authUserItem = localStorage.getItem('auth_user')
|
||||
const expiresAtItem = localStorage.getItem('expires_at')
|
||||
|
||||
if (authUserItem !== null && expiresAtItem !== null) {
|
||||
const expiresAt = new Date(expiresAtItem)
|
||||
|
||||
if (!isNaN(expiresAt.valueOf()) && expiresAt > new Date()) {
|
||||
try {
|
||||
return JSON.parse(authUserItem)
|
||||
} catch (_) { }
|
||||
}
|
||||
}
|
||||
|
||||
return null
|
||||
}
|
||||
|
||||
export function isAuthenticated() {
|
||||
return localStorage.getItem('jwt') !== null && getAuthUser() !== null
|
||||
}
|
||||
|
||||
```
|
||||
|
||||
When someone login, we save the JSON web token, expiration date of it and the current authenticated user on `localStorage`. This module uses that.
|
||||
|
||||
* `getAuthUser()` gets the authenticated user from `localStorage` making sure the JSON Web Token hasn’t expired yet.
|
||||
* `isAuthenticated()` makes use of the previous function to check whether it doesn’t return `null`.
|
||||
|
||||
|
||||
|
||||
### Fetch
|
||||
|
||||
Before continuing with the pages, I’ll code some HTTP utilities to work with the server API.
|
||||
|
||||
Let’s create a `static/js/http.js` file with the following content:
|
||||
```
|
||||
import { isAuthenticated } from './auth.js'
|
||||
|
||||
function get(url, headers) {
|
||||
return fetch(url, {
|
||||
headers: Object.assign(getAuthHeader(), headers),
|
||||
}).then(handleResponse)
|
||||
}
|
||||
|
||||
function post(url, body, headers) {
|
||||
return fetch(url, {
|
||||
method: 'POST',
|
||||
headers: Object.assign(getAuthHeader(), { 'content-type': 'application/json' }, headers),
|
||||
body: JSON.stringify(body),
|
||||
}).then(handleResponse)
|
||||
}
|
||||
|
||||
function getAuthHeader() {
|
||||
return isAuthenticated()
|
||||
? { authorization: `Bearer ${localStorage.getItem('jwt')}` }
|
||||
: {}
|
||||
}
|
||||
|
||||
export async function handleResponse(res) {
|
||||
const body = await res.clone().json().catch(() => res.text())
|
||||
const response = {
|
||||
url: res.url,
|
||||
statusCode: res.status,
|
||||
statusText: res.statusText,
|
||||
headers: res.headers,
|
||||
body,
|
||||
}
|
||||
if (!res.ok) throw Object.assign(
|
||||
new Error(body.message || body || res.statusText),
|
||||
response
|
||||
)
|
||||
return response
|
||||
}
|
||||
|
||||
export default {
|
||||
get,
|
||||
post,
|
||||
}
|
||||
|
||||
```
|
||||
|
||||
This module exports `get()` and `post()` functions. They are wrappers around the `fetch` API. Both functions inject an `Authorization: Bearer <token_here>` header to the request when the user is authenticated; that way the server can authenticate us.
|
||||
|
||||
### Welcome Page
|
||||
|
||||
Let’s move to the welcome page. Create a `static/js/pages/welcome-page.js` file with the following content:
|
||||
```
|
||||
const template = document.createElement('template')
|
||||
template.innerHTML = `
|
||||
<h1>Passwordless Demo</h1>
|
||||
<h2>Access</h2>
|
||||
<form id="access-form">
|
||||
<input type="email" placeholder="Email" autofocus required>
|
||||
<button type="submit">Send Magic Link</button>
|
||||
</form>
|
||||
`
|
||||
|
||||
export default function welcomePage() {
|
||||
const page = template.content.cloneNode(true)
|
||||
|
||||
page.getElementById('access-form')
|
||||
.addEventListener('submit', onAccessFormSubmit)
|
||||
|
||||
return page
|
||||
}
|
||||
|
||||
```
|
||||
|
||||
This page uses an `HTMLTemplateElement` for the view. It is just a simple form to enter the user’s email.
|
||||
|
||||
To not make this boring, I’ll skip error handling and just log them to console.
|
||||
|
||||
Now, let’s code that `onAccessFormSubmit()` function.
|
||||
```
|
||||
import http from '../http.js'
|
||||
|
||||
function onAccessFormSubmit(ev) {
|
||||
ev.preventDefault()
|
||||
|
||||
const form = ev.currentTarget
|
||||
const input = form.querySelector('input')
|
||||
const email = input.value
|
||||
|
||||
sendMagicLink(email).catch(err => {
|
||||
console.error(err)
|
||||
if (err.statusCode === 404 && wantToCreateAccount()) {
|
||||
runCreateUserProgram(email)
|
||||
}
|
||||
})
|
||||
}
|
||||
|
||||
function sendMagicLink(email) {
|
||||
return http.post('/api/passwordless/start', {
|
||||
email,
|
||||
redirectUri: location.origin + '/callback',
|
||||
}).then(() => {
|
||||
alert('Magic link sent. Go check your email inbox.')
|
||||
})
|
||||
}
|
||||
|
||||
function wantToCreateAccount() {
|
||||
return prompt('No user found. Do you want to create an account?')
|
||||
}
|
||||
|
||||
```
|
||||
|
||||
It does a `POST` request to `/api/passwordless/start` with the email and redirectUri in the body. In case it returns with `404 Not Found` status code, we’ll create a user.
|
||||
```
|
||||
function runCreateUserProgram(email) {
|
||||
const username = prompt("Enter username")
|
||||
if (username === null) return
|
||||
|
||||
http.post('/api/users', { email, username })
|
||||
.then(res => res.body)
|
||||
.then(user => sendMagicLink(user.email))
|
||||
.catch(console.error)
|
||||
}
|
||||
|
||||
```
|
||||
|
||||
The user creation program, first, ask for username and does a `POST` request to `/api/users` with the email and username in the body. On success, it sends a magic link for the user created.
|
||||
|
||||
### Callback Page
|
||||
|
||||
That was all the functionality for the access form, let’s move to the callback page. Create a `static/js/pages/callback-page.js` file with the following content:
|
||||
```
|
||||
import http from '../http.js'
|
||||
|
||||
const template = document.createElement('template')
|
||||
template.innerHTML = `
|
||||
<h1>Authenticating you 👀</h1>
|
||||
`
|
||||
|
||||
export default function callbackPage() {
|
||||
const page = template.content.cloneNode(true)
|
||||
|
||||
const hash = location.hash.substr(1)
|
||||
const fragment = new URLSearchParams(hash)
|
||||
for (const [k, v] of fragment.entries()) {
|
||||
fragment.set(decodeURIComponent(k), decodeURIComponent(v))
|
||||
}
|
||||
const jwt = fragment.get('jwt')
|
||||
const expiresAt = fragment.get('expires_at')
|
||||
|
||||
http.get('/api/auth_user', { authorization: `Bearer ${jwt}` })
|
||||
.then(res => res.body)
|
||||
.then(authUser => {
|
||||
localStorage.setItem('jwt', jwt)
|
||||
localStorage.setItem('auth_user', JSON.stringify(authUser))
|
||||
localStorage.setItem('expires_at', expiresAt)
|
||||
|
||||
location.replace('/')
|
||||
})
|
||||
.catch(console.error)
|
||||
|
||||
return page
|
||||
}
|
||||
|
||||
```
|
||||
|
||||
To remember… when clicking the magic link, we go to `/api/passwordless/verify_redirect` which redirect us to the redirect URI we pass (`/callback`) with the JWT and expiration date in the URL hash.
|
||||
|
||||
The callback page decodes the hash from the URL to extract those parameters to do a `GET` request to `/api/auth_user` with the JWT saving all the data to `localStorage`. Finally, it just redirects to home.
|
||||
|
||||
### Home Page
|
||||
|
||||
Create a `static/pages/home-page.js` file with the following content:
|
||||
```
|
||||
import { getAuthUser } from '../auth.js'
|
||||
|
||||
export default function homePage() {
|
||||
const authUser = getAuthUser()
|
||||
|
||||
const template = document.createElement('template')
|
||||
template.innerHTML = `
|
||||
<h1>Passwordless Demo</h1>
|
||||
<p>Welcome back, ${authUser.username} 👋</p>
|
||||
<button id="logout-button">Logout</button>
|
||||
`
|
||||
|
||||
const page = template.content
|
||||
|
||||
page.getElementById('logout-button')
|
||||
.addEventListener('click', logout)
|
||||
|
||||
return page
|
||||
}
|
||||
|
||||
function logout() {
|
||||
localStorage.clear()
|
||||
location.reload()
|
||||
}
|
||||
|
||||
```
|
||||
|
||||
This page greets the authenticated user and also has a logout button. The `logout()` function just clears `localStorage` and reloads the page.
|
||||
|
||||
There is it. I bet you already saw the [demo][4] before. Also, the source code is in the same [repository][5].
|
||||
|
||||
👋👋👋
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://nicolasparada.netlify.com/posts/passwordless-auth-client/
|
||||
|
||||
作者：[Nicolás Parada][a]
|
||||
选题：[lujun9972](https://github.com/lujun9972)
|
||||
译者：[译者ID](https://github.com/译者ID)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]:https://nicolasparada.netlify.com/
|
||||
[1]:https://nicolasparada.netlify.com/posts/passwordless-auth-server/
|
||||
[2]:https://nicolasparada.netlify.com/posts/javascript-client-router/
|
||||
[3]:https://developer.mozilla.org/en-US/docs/Web/HTTP/CORS
|
||||
[4]:https://go-passwordless-demo.herokuapp.com/
|
||||
[5]:https://github.com/nicolasparada/go-passwordless-demo
|
||||
156
sources/tech/20180516 How to Read Outlook Emails by Python.md
Normal file
156
sources/tech/20180516 How to Read Outlook Emails by Python.md
Normal file
@ -0,0 +1,156 @@
|
||||
translating by lujun9972
|
||||
How to Read Outlook Emails by Python
|
||||
======
|
||||
|
||||
|
||||
|
||||
when you start e-mail marketing , You need opt-in email address list. You have opt-in list. You are using email client software and If you can export your list from your email client, You will have good list.
|
||||
|
||||
Now I am trying to explain my codes to write all emails into test file from your outlook profile.
|
||||
|
||||
First you should import win32com.client, You need to install pywin32
|
||||
```
|
||||
pip install pywin32
|
||||
|
||||
```
|
||||
|
||||
We should connect to Outlook by MAPI
|
||||
```
|
||||
outlook = win32com.client.Dispatch("Outlook.Application").GetNamespace("MAPI")
|
||||
|
||||
```
|
||||
|
||||
Then we should get all accounts in your outlook profile.
|
||||
```
|
||||
accounts= win32com.client.Dispatch("Outlook.Application").Session.Accounts;
|
||||
|
||||
```
|
||||
|
||||
Then You need to get emails from inbox folder that is named emailleri_al.
|
||||
```
|
||||
def emailleri_al(folder):
|
||||
messages = folder.Items
|
||||
a=len(messages)
|
||||
if a>0:
|
||||
for message2 in messages:
|
||||
try:
|
||||
sender = message2.SenderEmailAddress
|
||||
if sender != "":
|
||||
print(sender, file=f)
|
||||
except:
|
||||
print("Ben hatayım")
|
||||
print(account.DeliveryStore.DisplayName)
|
||||
pass
|
||||
|
||||
try:
|
||||
message2.Save
|
||||
message2.Close(0)
|
||||
except:
|
||||
pass
|
||||
```
|
||||
|
||||
You should go to all account and get inbox folder and get emails
|
||||
```
|
||||
for account in accounts:
|
||||
global inbox
|
||||
inbox = outlook.Folders(account.DeliveryStore.DisplayName)
|
||||
print("****Account Name**********************************",file=f)
|
||||
print(account.DisplayName,file=f)
|
||||
print(account.DisplayName)
|
||||
print("***************************************************",file=f)
|
||||
folders = inbox.Folders
|
||||
|
||||
for folder in folders:
|
||||
print("****Folder Name**********************************", file=f)
|
||||
print(folder, file=f)
|
||||
print("*************************************************", file=f)
|
||||
emailleri_al(folder)
|
||||
a = len(folder.folders)
|
||||
|
||||
if a>0 :
|
||||
global z
|
||||
z = outlook.Folders(account.DeliveryStore.DisplayName).Folders(folder.name)
|
||||
x = z.Folders
|
||||
for y in x:
|
||||
emailleri_al(y)
|
||||
print("****Folder Name**********************************", file=f)
|
||||
print("..."+y.name,file=f)
|
||||
print("*************************************************", file=
|
||||
```
|
||||
|
||||
All Code is as the following
|
||||
```
|
||||
import win32com.client
|
||||
import win32com
|
||||
import os
|
||||
import sys
|
||||
|
||||
f = open("testfile.txt","w+")
|
||||
|
||||
outlook = win32com.client.Dispatch("Outlook.Application").GetNamespace("MAPI")
|
||||
accounts= win32com.client.Dispatch("Outlook.Application").Session.Accounts;
|
||||
|
||||
def emailleri_al(folder):
|
||||
messages = folder.Items
|
||||
a=len(messages)
|
||||
if a>0:
|
||||
for message2 in messages:
|
||||
try:
|
||||
sender = message2.SenderEmailAddress
|
||||
if sender != "":
|
||||
print(sender, file=f)
|
||||
except:
|
||||
print("Error")
|
||||
print(account.DeliveryStore.DisplayName)
|
||||
pass
|
||||
|
||||
try:
|
||||
message2.Save
|
||||
message2.Close(0)
|
||||
except:
|
||||
pass
|
||||
|
||||
|
||||
|
||||
for account in accounts:
|
||||
global inbox
|
||||
inbox = outlook.Folders(account.DeliveryStore.DisplayName)
|
||||
print("****Account Name**********************************",file=f)
|
||||
print(account.DisplayName,file=f)
|
||||
print(account.DisplayName)
|
||||
print("***************************************************",file=f)
|
||||
folders = inbox.Folders
|
||||
|
||||
for folder in folders:
|
||||
print("****Folder Name**********************************", file=f)
|
||||
print(folder, file=f)
|
||||
print("*************************************************", file=f)
|
||||
emailleri_al(folder)
|
||||
a = len(folder.folders)
|
||||
|
||||
if a>0 :
|
||||
global z
|
||||
z = outlook.Folders(account.DeliveryStore.DisplayName).Folders(folder.name)
|
||||
x = z.Folders
|
||||
for y in x:
|
||||
emailleri_al(y)
|
||||
print("****Folder Name**********************************", file=f)
|
||||
print("..."+y.name,file=f)
|
||||
print("*************************************************", file=f)
|
||||
|
||||
|
||||
|
||||
print("Finished Succesfully")
|
||||
```
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://www.codementor.io/aliacetrefli/how-to-read-outlook-emails-by-python-jkp2ksk95
|
||||
|
||||
作者：[A.A. Cetrefli][a]
|
||||
选题：[lujun9972](https://github.com/lujun9972)
|
||||
译者：[lujun9972](https://github.com/lujun9972)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]:https://www.codementor.io/aliacetrefli
|
||||
70
sources/tech/20180519 Python Debugging Tips.md
Normal file
70
sources/tech/20180519 Python Debugging Tips.md
Normal file
@ -0,0 +1,70 @@
|
||||
Python Debugging Tips
|
||||
======
|
||||
When it comes to debugging, there’s a lot of choices that you can make. It is hard to give generic advice that always works (other than “Have you tried turning it off and back on?”).
|
||||
|
||||
Here are a few of my favorite Python Debugging tips.
|
||||
|
||||
### Make a branch
|
||||
|
||||
Trust me on this. Even if you never intend to commit the changes back upstream, you will be glad your experiments are contained within their own branch.
|
||||
|
||||
If nothing else, it makes cleanup a lot easier!
|
||||
|
||||
### Install pdb++
|
||||
|
||||
Seriously. It makes you life easier if you are on the command line.
|
||||
|
||||
All that pdb++ does is replace the standard pdb module with 100% PURE AWESOMENESS. Here’s what you get when you `pip install pdbpp`:
|
||||
|
||||
* A Colorized prompt!
|
||||
* tab completion! (perfect for poking around!)
|
||||
* It slices! It dices!
|
||||
|
||||
|
||||
|
||||
Ok, maybe the last one is a little bit much… But in all seriousness, installing pdb++ is well worth your time.
|
||||
|
||||
### Poke around
|
||||
|
||||
Sometimes the best approach is to just mess around and see what happens. Put a break point in an “obvious” spot and make sure it gets hit. Pepper the code with `print()` and/or `logging.debug()` statements and see where the code execution goes.
|
||||
|
||||
Examine the arguments being passed into your functions. Check the versions of the libraries (if things are getting really desperate).
|
||||
|
||||
### Only change one thing at a time
|
||||
|
||||
Once you are poking around a bit you are going to get ideas on things you could do. But before you start slinging code, take a step back and think about what you could change, and then only change 1 thing.
|
||||
|
||||
Once you’ve made the change, then test and see if you are closer to resolving the issue. If not, change the thing back, and try something else.
|
||||
|
||||
Changing only one thing allows you to know what does and doesn’t work. Plus once you do get it working, your new commit is going to be much smaller (because there will be less changes).
|
||||
|
||||
This is pretty much what one does in the Scientific Process: only change one variable at a time. By allowing yourself to see and measure the results of one change you will save your sanity and arrive at a working solution faster.
|
||||
|
||||
### Assume nothing, ask questions
|
||||
|
||||
Occasionally a developer (not you of course!) will be in a hurry and whip out some questionable code. When you go through to debug this code you need to stop and make sure you understand what it is trying to accomplish.
|
||||
|
||||
Make no assumptions. Just because the code is in the `model.py` file doesn’t mean it won’t try to render some HTML.
|
||||
|
||||
Likewise, double check all of your external connections before you do anything destructive! Going to delete some configuration data? MAKE SURE YOU ARE NOT CONNECTED TO YOUR PRODUCTION SYSTEM.
|
||||
|
||||
### Be clever, but not too clever
|
||||
|
||||
Sometimes we write code that is so amazingly awesome it is not obvious how it does what it does.
|
||||
|
||||
While we might feel smart when we publish that code, more often than not we will wind up feeling dumb later on when the code breaks and we have to remember how it works to figure out why it isn’t working.
|
||||
|
||||
Keep an eye out for any sections of code that look either overly complicated and long, or extremely short. These could be places where complexity is hiding and causing your bugs.
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://pythondebugging.com/articles/python-debugging-tips
|
||||
|
||||
作者：[PythonDebugging.com][a]
|
||||
选题：[lujun9972](https://github.com/lujun9972)
|
||||
译者：[译者ID](https://github.com/译者ID)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]:https://pythondebugging.com
|
||||
@ -1,190 +0,0 @@
|
||||
How to load or unload a Linux kernel module
|
||||
======
|
||||
|
||||
|
||||
|
||||
This article is excerpted from chapter 15 of [Linux in Action][1], published by Manning.
|
||||
|
||||
Linux manages hardware peripherals using kernel modules. Here's how that works.
|
||||
|
||||
A running Linux kernel is one of those things you don't want to upset. After all, the kernel is the software that drives everything your computer does. Considering how many details have to be simultaneously managed on a live system, it's better to leave the kernel to do its job with as few distractions as possible. But if it's impossible to make even small changes to the compute environment without rebooting the whole system, then plugging in a new webcam or printer could cause a painful disruption to your workflow. Having to reboot each time you add a device to get the system to recognize it is hardly efficient.
|
||||
|
||||
To create an effective balance between the opposing virtues of stability and usability, Linux isolates the kernel, but lets you add specific functionality on the fly through loadable kernel modules (LKMs). As shown in the figure below, you can think of a module as a piece of software that tells the kernel where to find a device and what to do with it. In turn, the kernel makes the device available to users and processes and oversees its operation.
|
||||
|
||||
![Kernel modules][3]
|
||||
|
||||
Kernel modules act as translators between devices and the Linux kernel.
|
||||
|
||||
There's nothing stopping you from writing your own module to support a device exactly the way you'd like it, but why bother? The Linux module library is already so robust that there's usually no need to roll your own. And the vast majority of the time, Linux will automatically load a new device's module without you even knowing it.
|
||||
|
||||
Still, there are times when, for some reason, it doesn't happen by itself. (You don't want to leave that hiring manager impatiently waiting for your smiling face to join the video conference job interview for too long.) To help things along, you'll want to understand a bit more about kernel modules and, in particular, how to find the actual module that will run your peripheral and then how to manually activate it.
|
||||
|
||||
### Finding kernel modules
|
||||
|
||||
By accepted convention, modules are files with a .ko (kernel object) extension that live beneath the `/lib/modules/` directory. Before you navigate all the way down to those files, however, you'll probably have to make a choice. Because you're given the option at boot time of loading one from a list of releases, the specific software needed to support your choice (including the kernel modules) has to exist somewhere. Well, `/lib/modules`/ is one of those somewheres. And that's where you'll find directories filled with the modules for each available Linux kernel release; for example:
|
||||
```
|
||||
$ ls /lib/modules
|
||||
|
||||
4.4.0-101-generic
|
||||
|
||||
4.4.0-103-generic
|
||||
|
||||
4.4.0-104-generic
|
||||
|
||||
```
|
||||
|
||||
In my case, the active kernel is the version with the highest release number (4.4.0-104-generic), but there's no guarantee that that'll be the same for you (kernels are frequently updated). If you're going to be doing some work with modules that you'd like to use on a live system, you need to be sure you've got the right directory tree.
|
||||
|
||||
`uname -r` (the `-r` specifies the kernel release number from within the system information that would normally be displayed):
|
||||
```
|
||||
$ uname -r
|
||||
|
||||
4.4.0-104-generic
|
||||
|
||||
```
|
||||
|
||||
Good news: there's a reliable trick. Rather than identifying the directory by name and hoping you'll get the right one, use the system variable that always points to the name of the active kernel. You can invoke that variable using(thespecifies the kernel release number from within the system information that would normally be displayed):
|
||||
|
||||
With that information, you can incorporate `uname` into your filesystem references using a process known as command substitution. To navigate to the right directory, for instance, you'd add it to `/lib/modules`. To tell Linux that "uname" isn't a filesystem location, enclose the `uname` part in backticks, like this:
|
||||
```
|
||||
$ ls /lib/modules/`uname -r`
|
||||
|
||||
build modules.alias modules.dep modules.softdep
|
||||
|
||||
initrd modules.alias.bin modules.dep.bin modules.symbols
|
||||
|
||||
kernel modules.builtin modules.devname modules.symbols.bin
|
||||
|
||||
misc modules.builtin.bin modules.order vdso
|
||||
|
||||
```
|
||||
|
||||
You'll find most of the modules organized within their subdirectories beneath the `kernel/` directory. Take a few minutes to browse through those directories to get an idea of how things are arranged and what's available. The filenames usually give you a good idea of what you're looking at.
|
||||
```
|
||||
$ ls /lib/modules/`uname -r`/kernel
|
||||
|
||||
arch crypto drivers fs kernel lib mm
|
||||
|
||||
net sound ubuntu virt zfs
|
||||
|
||||
```
|
||||
|
||||
That's one way to locate kernel modules; actually, it's the quick and dirty way to go about it. But it's not the only way. If you want to get the complete set, you can list all currently loaded modules, along with some basic information, by using `lsmod`. The first column of this truncated output (there would be far too many to list here) is the module name, followed by the file size and number, and then the names of other modules on which each is dependent:
|
||||
```
|
||||
$ lsmod
|
||||
|
||||
[...]
|
||||
|
||||
vboxdrv 454656 3 vboxnetadp,vboxnetflt,vboxpci
|
||||
|
||||
rt2x00usb 24576 1 rt2800usb
|
||||
|
||||
rt2800lib 94208 1 rt2800usb
|
||||
|
||||
[...]
|
||||
|
||||
```
|
||||
|
||||
How many are far too many? Well, let's run `lsmod` once again, but this time piping the output to `wc -l` to get a count of the lines:
|
||||
```
|
||||
$ lsmod | wc -l
|
||||
|
||||
113
|
||||
|
||||
```
|
||||
|
||||
Those are the loaded modules. How many are available in total? Running `modprobe -c` and counting the lines will give us that number:
|
||||
```
|
||||
$ modprobe -c | wc -l
|
||||
|
||||
33350
|
||||
|
||||
```
|
||||
|
||||
There are 33,350 available modules!?! It looks like someone's been working hard over the years to provide us with the software to run our physical devices.
|
||||
|
||||
Note: On some systems, you might encounter customized modules that are referenced either with their unique entries in the `/etc/modules` file or as a configuration file saved to `/etc/modules-load.d/`. The odds are that such modules are the product of local development projects, perhaps involving cutting-edge experiments. Either way, it's good to have some idea of what it is you're looking at.
|
||||
|
||||
That's how you find modules. Your next job is to figure out how to manually load an inactive module if, for some reason, it didn't happen on its own.
|
||||
|
||||
### Manually loading kernel modules
|
||||
|
||||
Before you can load a kernel module, logic dictates that you'll have to confirm it exists. And before you can do that, you'll need to know what it's called. Getting that part sometimes requires equal parts magic and luck and some help from of the hard work of online documentation authors.
|
||||
|
||||
I'll illustrate the process by describing a problem I ran into some time back. One fine day, for a reason that still escapes me, the WiFi interface on a laptop stopped working. Just like that. Perhaps a software update knocked it out. Who knows? I ran `lshw -c network` and was treated to this very strange information:
|
||||
```
|
||||
network UNCLAIMED
|
||||
|
||||
AR9485 Wireless Network Adapter
|
||||
|
||||
```
|
||||
|
||||
Linux recognized the interface (the Atheros AR9485) but listed it as unclaimed. Well, as they say, "When the going gets tough, the tough search the internet." I ran a search for atheros ar9 linux module and, after sifting through pages and pages of five- and even 10-year-old results advising me to either write my own module or just give up, I finally discovered that (with Ubuntu 16.04, at least) a working module existed. Its name is ath9k.
|
||||
|
||||
Yes! The battle's as good as won! Adding a module to the kernel is a lot easier than it sounds. To double check that it's available, you can run `find` against the module's directory tree, specify `-type f` to tell Linux you're looking for a file, and then add the string `ath9k` along with a glob asterisk to include all filenames that start with your string:
|
||||
```
|
||||
$ find /lib/modules/$(uname -r) -type f -name ath9k*
|
||||
|
||||
/lib/modules/4.4.0-97-generic/kernel/drivers/net/wireless/ath/ath9k/ath9k_common.ko
|
||||
|
||||
/lib/modules/4.4.0-97-generic/kernel/drivers/net/wireless/ath/ath9k/ath9k.ko
|
||||
|
||||
/lib/modules/4.4.0-97-generic/kernel/drivers/net/wireless/ath/ath9k/ath9k_htc.ko
|
||||
|
||||
/lib/modules/4.4.0-97-generic/kernel/drivers/net/wireless/ath/ath9k/ath9k_hw.ko
|
||||
|
||||
```
|
||||
|
||||
Just one more step, load the module:
|
||||
```
|
||||
# modprobe ath9k
|
||||
|
||||
```
|
||||
|
||||
That's it. No reboots. No fuss.
|
||||
|
||||
Here's one more example to show you how to work with active modules that have become corrupted. There was a time when using my Logitech webcam with a particular piece of software would make the camera inaccessible to any other programs until the next system boot. Sometimes I needed to open the camera in a different application but didn't have the time to shut down and start up again. (I run a lot of applications, and getting them all in place after booting takes some time.)
|
||||
|
||||
Because this module is presumably active, using `lsmod` to search for the word video should give me a hint about the name of the relevant module. In fact, it's better than a hint: The only module described with the word video is uvcvideo (as you can see in the following):
|
||||
```
|
||||
$ lsmod | grep video
|
||||
|
||||
uvcvideo 90112 0
|
||||
|
||||
videobuf2_vmalloc 16384 1 uvcvideo
|
||||
|
||||
videobuf2_v4l2 28672 1 uvcvideo
|
||||
|
||||
videobuf2_core 36864 2 uvcvideo,videobuf2_v4l2
|
||||
|
||||
videodev 176128 4 uvcvideo,v4l2_common,videobuf2_core,videobuf2_v4l2
|
||||
|
||||
media 24576 2 uvcvideo,videodev
|
||||
|
||||
```
|
||||
|
||||
There was probably something I could have controlled for that was causing the crash, and I guess I could have dug a bit deeper to see if I could fix things the right way. But you know how it is; sometimes you don't care about the theory and just want your device working. So I used `rmmod` to kill the uvcvideo module and `modprobe` to start it up again all nice and fresh:
|
||||
```
|
||||
# rmmod uvcvideo
|
||||
|
||||
# modprobe uvcvideo
|
||||
|
||||
```
|
||||
|
||||
Again: no reboots. No stubborn blood stains.
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://opensource.com/article/18/5/how-load-or-unload-linux-kernel-module
|
||||
|
||||
作者：[David Clinto][a]
|
||||
选题：[lujun9972](https://github.com/lujun9972)
|
||||
译者：[译者ID](https://github.com/译者ID)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]:https://opensource.com/users/dbclinton
|
||||
[1]:https://www.manning.com/books/linux-in-action?a_aid=bootstrap-it&a_bid=4ca15fc9&chan=opensource
|
||||
[2]:/file/397906
|
||||
[3]:https://opensource.com/sites/default/files/uploads/kernels.png (Kernel modules)
|
||||
@ -0,0 +1,84 @@
|
||||
3 open source alternatives to Adobe Lightroom
|
||||
======
|
||||
|
||||
|
||||
|
||||
You wouldn't be wrong to wonder whether the smartphone, that modern jack-of-all-trades, is taking over photography. While that might be valid in the point-and-shoot camera market, there are a sizeable number of photography professionals and hobbyists who recognize that a camera that fits in your pocket can never replace a high-end DSLR camera and the depth, clarity, and realism of its photos.
|
||||
|
||||
All of that power comes with a small price in terms of convenience; like negatives from traditional film cameras, the [raw image][1] files produced by DSLRs must be processed before they can be edited or printed. For this, a digital image processing application is indispensable, and the go-to application has been Adobe Lightroom. But for many reasons—including its expensive, subscription-based pricing model and its proprietary license—there's a lot of interest in open source and other alternatives.
|
||||
|
||||
Lightroom has two main functions: processing raw image files and digital asset management (DAM)—organizing images with tags, ratings, and other metadata to make it easier to keep track of them.
|
||||
|
||||
In this article, we'll look at three open source image processing applications: Darktable, LightZone, and RawTherapee. All of them have DAM capabilities, but none has Lightroom's machine learning-based image categorization and tagging features. If you're looking for more information about open source DAM software, check out Terry Hancock's article "[Digital asset management for an open movie project][2]," where he shares his research on software to organize multimedia files for his [_Lunatics!_][3] open movie project.
|
||||
|
||||
### Darktable
|
||||
|
||||
![Darktable][4]
|
||||
|
||||
Like the other applications on our list, [darktable][5] processes raw images into usable file formats—it exports into JPEG, PNG, TIFF, PPM, PFM, and EXR, and it also supports Google and Facebook web albums, Flickr uploads, email attachments, and web gallery creation.
|
||||
|
||||
Its 61 image operation modules allow you to adjust contrast, tone, exposure, color, noise, etc.; add watermarks; crop and rotate; and much more. As with the other applications described in this article, those edits are "non-destructive"—that is, your original raw image is preserved no matter how many tweaks and modifications you make.
|
||||
|
||||
Darktable imports raw images from more than 400 cameras plus JPEG, CR2, DNG, OpenEXR, and PFM; images are managed in a database so you can filter and search using metadata including tags, ratings, and color. It's also available in 21 languages and is supported on Linux, MacOS, BSD, Solaris 11/GNOME, and Windows. (The [Windows port][6] is new, and darktable warns it may have "rough edges or missing functionality" compared to other versions.)
|
||||
|
||||
Darktable is licensed under [GPLv3][7]; you can learn more by perusing its [features][8], viewing the [user manual][9], or accessing its [source code][10] on GitHub.
|
||||
|
||||
### LightZone
|
||||
|
||||
![LightZone's tool stack][11]
|
||||
|
||||
As a non-destructive raw image processing tool, [LightZone][12] is similar to the other two applications on this list: it's cross-platform, operating on Windows, MacOS, and Linux, and it supports JPG and TIFF images in addition to raw. But it's also unique in several ways.
|
||||
|
||||
For one thing, it started out in 2005 as a proprietary image processing tool and later became an open source project under a BSD license. Also, before you can download the application, you must register for a free account; this is so the LightZone development community can track downloads and build the community. (Approval is quick and automated, so it's not a large barrier.)
|
||||
|
||||
Another difference is that image modifications are done using stackable tools, rather than filters (like most image-editing applications); tool stacks can be rearranged or removed, as well as saved and copied to a batch of images. You can also edit certain parts of an image using a vector-based tool or by selecting pixels based on color or brightness.
|
||||
|
||||
You can get more information on LightZone by searching its [forums][13] or accessing its [source code][14] on GitHub.
|
||||
|
||||
### RawTherapee
|
||||
|
||||
![RawTherapee][15]
|
||||
|
||||
[RawTherapee][16] is another popular open source ([GPL][17]) raw image processor worth your attention. Like darktable and LightZone, it is cross-platform (Windows, MacOS, and Linux) and implements edits in a non-destructive fashion, so you maintain access to your original raw image file no matter what filters or changes you make.
|
||||
|
||||
RawTherapee uses a panel-based interface, including a history panel to keep track of your changes and revert to a previous point; a snapshot panel that allows you to work with multiple versions of a photo; and scrollable tool panels to easily select a tool without worrying about accidentally using the wrong one. Its tools offer a wide variety of exposure, color, detail, transformation, and demosaicing features.
|
||||
|
||||
The application imports raw files from most cameras and is localized to more than 25 languages, making it widely usable. Features like batch processing and [SSE][18] optimizations improve speed and CPU performance.
|
||||
|
||||
RawTherapee offers many other [features][19]; check out its [documentation][20] and [source code][21] for details.
|
||||
|
||||
Do you use another open source raw image processing tool in your photography? Do you have any related tips or suggestions for other photographers? If so, please share your recommendations in the comments.
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://opensource.com/alternatives/adobe-lightroom
|
||||
|
||||
作者：[Opensource.com][a]
|
||||
选题：[lujun9972](https://github.com/lujun9972)
|
||||
译者：[译者ID](https://github.com/译者ID)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]:https://opensource.com
|
||||
[1]:https://en.wikipedia.org/wiki/Raw_image_format
|
||||
[2]:https://opensource.com/article/18/3/movie-open-source-software
|
||||
[3]:http://lunatics.tv/
|
||||
[4]:https://opensource.com/sites/default/files/styles/panopoly_image_original/public/uploads/raw-image-processors_darkroom1.jpg?itok=0fjk37tC (Darktable)
|
||||
[5]:http://www.darktable.org/
|
||||
[6]:https://www.darktable.org/about/faq/#faq-windows
|
||||
[7]:https://github.com/darktable-org/darktable/blob/master/LICENSE
|
||||
[8]:https://www.darktable.org/about/features/
|
||||
[9]:https://www.darktable.org/resources/
|
||||
[10]:https://github.com/darktable-org/darktable
|
||||
[11]:https://opensource.com/sites/default/files/styles/panopoly_image_original/public/uploads/raw-image-processors_lightzone1tookstack.jpg?itok=1e3s85CZ (LightZone's tool stack)
|
||||
[12]:http://www.lightzoneproject.org/
|
||||
[13]:http://www.lightzoneproject.org/Forum
|
||||
[14]:https://github.com/ktgw0316/LightZone
|
||||
[15]:https://opensource.com/sites/default/files/styles/panopoly_image_original/public/uploads/raw-image-processors_rawtherapee.jpg?itok=meiuLxPw (RawTherapee)
|
||||
[16]:http://rawtherapee.com/
|
||||
[17]:https://github.com/Beep6581/RawTherapee/blob/dev/LICENSE.txt
|
||||
[18]:https://en.wikipedia.org/wiki/Streaming_SIMD_Extensions
|
||||
[19]:http://rawpedia.rawtherapee.com/Features
|
||||
[20]:http://rawpedia.rawtherapee.com/Main_Page
|
||||
[21]:https://github.com/Beep6581/RawTherapee
|
||||
185
sources/tech/20180611 How to partition a disk in Linux.md
Normal file
185
sources/tech/20180611 How to partition a disk in Linux.md
Normal file
@ -0,0 +1,185 @@
|
||||
How to partition a disk in Linux
|
||||
======
|
||||
|
||||
|
||||
Creating and deleting partitions in Linux is a regular practice because storage devices (such as hard drives and USB drives) must be structured in some way before they can be used. In most cases, large storage devices are divided into separate sections called partitions. Partitioning also allows you to divide your hard drive into isolated sections, where each section behaves as its own hard drive. Partitioning is particularly useful if you run multiple operating systems.
|
||||
|
||||
There are lots of powerful tools for creating, removing, and otherwise manipulating disk partitions in Linux. In this article, I'll explain how to use the `parted` command, which is particularly useful with large disk devices and many disk partitions. Differences between `parted` and the more common `fdisk` and `cfdisk` commands include:
|
||||
|
||||
* **GPT format:** The `parted` command can create a Globally Unique Identifiers Partition Table [GPT][1]), while `fdisk` and `cfdisk` are limited to DOS partition tables.
|
||||
* **Larger disks:** A DOS partition table can format up to 2TB of disk space, although up to 16TB is possible in some cases. However, a GPT partition table can address up to 8ZiB of space.
|
||||
* **More partitions:** Using primary and extended partitions, DOS partition tables allow only 16 partitions. With GPT, you get up to 128 partitions by default and can choose to have many more.
|
||||
* **Reliability:** Only one copy of the partition table is stored in a DOS partition. GPT keeps two copies of the partition table (at the beginning and the end of the disk). The GPT also uses a [CRC][2] checksum to check the partition table integrity, which is not done with DOS partitions.
|
||||
|
||||
|
||||
|
||||
With today's larger disks and the need for more flexibility in working with them, using `parted` to work with disk partitions is recommended. Most of the time, disk partition tables are created as part of the operating system installation process. Direct use of the `parted` command is most useful when adding a storage device to an existing system.
|
||||
|
||||
### Give 'parted' a try
|
||||
|
||||
`parted` command. To try these steps, I strongly recommend using a brand new storage device or one where you don't mind wiping out the contents.
|
||||
|
||||
The following explains the process of partitioning a storage device with thecommand. To try these steps, I strongly recommend using a brand new storage device or one where you don't mind wiping out the contents.
|
||||
|
||||
**1\. List the partitions:** Use `parted -l` to identify the storage device you want to partition. Typically, the first hard disk (`/dev/sda` or `/dev/vda`) will contain the operating system, so look for another disk to find the one you want (e.g., `/dev/sdb`, `/dev/sdc`, `/dev/vdb`, `/dev/vdc`, etc.).
|
||||
```
|
||||
$ sudo parted -l
|
||||
|
||||
[sudo] password for daniel:
|
||||
|
||||
Model: ATA RevuAhn_850X1TU5 (scsi)
|
||||
|
||||
Disk /dev/vdc: 512GB
|
||||
|
||||
Sector size (logical/physical): 512B/512B
|
||||
|
||||
Partition Table: msdos
|
||||
|
||||
Disk Flags:
|
||||
|
||||
|
||||
|
||||
Number Start End Size Type File system Flags
|
||||
|
||||
1 1049kB 525MB 524MB primary ext4 boot
|
||||
|
||||
2 525MB 512GB 512GB primary lvm
|
||||
|
||||
```
|
||||
|
||||
**2\. Open the storage device:** Use `parted` to begin working with the selected storage device. In this example, the device is the third disk on a virtual system (`/dev/vdc`). It is important to indicate the specific device you want to use. If you just type `parted` with no device name, it will randomly select a storage device to modify.
|
||||
```
|
||||
$ sudo parted /dev/vdc
|
||||
|
||||
GNU Parted 3.2
|
||||
|
||||
Using /dev/vdc
|
||||
|
||||
Welcome to GNU Parted! Type 'help' to view a list of commands.
|
||||
|
||||
(parted)
|
||||
|
||||
```
|
||||
|
||||
**3\. Set the partition table:** Set the partition table type to GPT, then type "Yes" to accept it.
|
||||
```
|
||||
(parted) mklabel gpt
|
||||
|
||||
Warning: the existing disk label on /dev/vdc will be destroyed
|
||||
|
||||
and all data on this disk will be lost. Do you want to continue?
|
||||
|
||||
Yes/No? Yes
|
||||
|
||||
```
|
||||
|
||||
The `mklabel` and `mktable` commands are used for the same purpose (making a partition table on a storage device). The supported partition tables are: aix, amiga, bsd, dvh, gpt, mac, ms-dos, pc98, sun, and loop. Remember `mklabel` will not make a partition, rather it will make a partition table.
|
||||
|
||||
**4\. Review the partition table:** Show information about the storage device.
|
||||
```
|
||||
(parted) print
|
||||
|
||||
Model: Virtio Block Device (virtblk)
|
||||
|
||||
Disk /dev/vdc: 1396MB
|
||||
|
||||
Sector size (logical/physical): 512B/512B
|
||||
|
||||
Partition Table: gpt
|
||||
|
||||
Disk Flags:
|
||||
|
||||
Number Start End Size File system Name Flags
|
||||
|
||||
```
|
||||
|
||||
**5\. Get help:** To find out how to make a new partition, type: `(parted) help mkpart`.
|
||||
```
|
||||
(parted) help mkpart
|
||||
|
||||
mkpart PART-TYPE [FS-TYPE] START END make a partition
|
||||
|
||||
|
||||
|
||||
PART-TYPE is one of: primary, logical, extended
|
||||
|
||||
FS-TYPE is one of: btrfs, nilfs2, ext4, ext3, ext2, fat32, fat16, hfsx, hfs+, hfs, jfs, swsusp,
|
||||
|
||||
linux-swap(v1), linux-swap(v0), ntfs, reiserfs, hp-ufs, sun-ufs, xfs, apfs2, apfs1, asfs, amufs5,
|
||||
|
||||
amufs4, amufs3, amufs2, amufs1, amufs0, amufs, affs7, affs6, affs5, affs4, affs3, affs2, affs1,
|
||||
|
||||
affs0, linux-swap, linux-swap(new), linux-swap(old)
|
||||
|
||||
START and END are disk locations, such as 4GB or 10%. Negative values count from the end of the
|
||||
|
||||
disk. For example, -1s specifies exactly the last sector.
|
||||
|
||||
|
||||
|
||||
'mkpart' makes a partition without creating a new file system on the partition. FS-TYPE may be
|
||||
|
||||
specified to set an appropriate partition ID.
|
||||
|
||||
```
|
||||
|
||||
**6\. Make a partition:** To make a new partition (in this example, 1,396MB on partition 0), type the following:
|
||||
```
|
||||
(parted) mkpart primary 0 1396MB
|
||||
|
||||
|
||||
|
||||
Warning: The resulting partition is not properly aligned for best performance
|
||||
|
||||
Ignore/Cancel? I
|
||||
|
||||
|
||||
|
||||
(parted) print
|
||||
|
||||
Model: Virtio Block Device (virtblk)
|
||||
|
||||
Disk /dev/vdc: 1396MB
|
||||
|
||||
Sector size (logical/physical): 512B/512B
|
||||
|
||||
Partition Table: gpt
|
||||
|
||||
Disk Flags:
|
||||
|
||||
Number Start End Size File system Name Flags
|
||||
|
||||
1 17.4kB 1396MB 1396MB primary
|
||||
|
||||
```
|
||||
|
||||
Filesystem type (fstype) will not create an ext4 filesystem on `/dev/vdc1`. A DOS partition table's partition types are primary, logical, and extended. In a GPT partition table, the partition type is used as the partition name. Providing a partition name under GPT is a must; in the above example, primary is the name, not the partition type.
|
||||
|
||||
**7\. Save and quit:** Changes are automatically saved when you quit `parted`. To quit, type the following:
|
||||
```
|
||||
(parted) quit
|
||||
|
||||
Information: You may need to update /etc/fstab.
|
||||
|
||||
$
|
||||
|
||||
```
|
||||
|
||||
### Words to the wise
|
||||
|
||||
Make sure to identify the correct disk before you begin changing its partition table when you add a new storage device. If you mistakenly change the disk partition that contains your computer's operating system, you could make your system unbootable.
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://opensource.com/article/18/6/how-partition-disk-linux
|
||||
|
||||
作者：[Daniel Oh][a]
|
||||
选题：[lujun9972](https://github.com/lujun9972)
|
||||
译者：[译者ID](https://github.com/译者ID)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]:https://opensource.com/users/daniel-oh
|
||||
[1]:https://en.wikipedia.org/wiki/GUID_Partition_Table
|
||||
[2]:https://en.wikipedia.org/wiki/Cyclic_redundancy_check
|
||||
@ -0,0 +1,133 @@
|
||||
Turn Your Raspberry Pi into a Tor Relay Node
|
||||
======
|
||||
|
||||
|
||||
|
||||
If you’re anything like me, you probably got yourself a first- or second-generation Raspberry Pi board when they first came out, played with it for a while, but then shelved it and mostly forgot about it. After all, unless you’re a robotics enthusiast, you probably don’t have that much use for a computer with a pretty slow processor and 256 megabytes of RAM. This is not to say that there aren’t cool things you can do with one of these, but between work and other commitments, I just never seem to find the right time for some good old nerding out.
|
||||
|
||||
However, if you would like to put it to good use without sacrificing too much of your time or resources, you can turn your old Raspberry Pi into a perfectly functioning Tor relay node.
|
||||
|
||||
### What is a Tor Relay node
|
||||
|
||||
You have probably heard about the [Tor project][1] before, but just in case you haven’t, here’s a very quick summary. The name “Tor” stands for “The Onion Router” and it is a technology created to combat online tracking and other privacy violations.
|
||||
|
||||
Everything you do on the Internet leaves a set of digital footprints in every piece of equipment that your IP packets traverse: all of the switches, routers, load balancers and destination websites log the IP address from which your session originated and the IP address of the internet resource you are accessing (and often its hostname, [even when using HTTPS][2]). If you’re browsing from home, then your IP can be directly mapped to your household. If you’re using a VPN service ([as you should be][3]), then your IP can be mapped to your VPN provider, and then they are the ones who can map it to your household. In any case, odds are that someone somewhere is assembling an online profile on you based on the sites you visit and how much time you spend on each of them. Such profiles are then sold, aggregated with matching profiles collected from other services, and then monetized by ad networks. At least, that’s the optimist’s view of how that data is used -- I’m sure you can think of many examples of how your online usage profiles can be used against you in much more nefarious ways.
|
||||
|
||||
The Tor project attempts to provide a solution to this problem by making it impossible (or, at least, unreasonably difficult) to trace the endpoints of your IP session. Tor achieves this by bouncing your connection through a chain of anonymizing relays, consisting of an entry node, relay node, and exit node:
|
||||
|
||||
1. The **entry node** only knows your IP address, and the IP address of the relay node, but not the final destination of the request;
|
||||
|
||||
2. The **relay node** only knows the IP address of the entry node and the IP address of the exit node, and neither the origin nor the final destination
|
||||
|
||||
3. The **exit node** **** only knows the IP address of the relay node and the final destination of the request; it is also the only node that can decrypt the traffic before sending it over to its final destination
|
||||
|
||||
|
||||
|
||||
|
||||
Relay nodes play a crucial role in this exchange because they create a cryptographic barrier between the source of the request and the destination. Even if exit nodes are controlled by adversaries intent on stealing your data, they will not be able to know the source of the request without controlling the entire Tor relay chain.
|
||||
|
||||
As long as there are plenty of relay nodes, your privacy when using the Tor network remains protected -- which is why I heartily recommend that you set up and run a relay node if you have some home bandwidth to spare.
|
||||
|
||||
#### Things to keep in mind regarding Tor relays
|
||||
|
||||
A Tor relay node only receives encrypted traffic and sends encrypted traffic -- it never accesses any other sites or resources online, so you do not need to worry that someone will browse any worrisome sites directly from your home IP address. Having said that, if you reside in a jurisdiction where offering anonymity-enhancing services is against the law, then, obviously, do not operate your own Tor relay. You may also want to check if operating a Tor relay is against the terms and conditions of your internet access provider.
|
||||
|
||||
### What you will need
|
||||
|
||||
* A Raspberry Pi (any model/generation) with some kind of enclosure
|
||||
|
||||
* An SD card with [Raspbian Stretch Lite][4]
|
||||
|
||||
* An ethernet cable
|
||||
|
||||
* A micro-USB cable for power
|
||||
|
||||
* A keyboard and an HDMI-capable monitor (to use during the setup)
|
||||
|
||||
|
||||
|
||||
|
||||
This guide will assume that you are setting this up on your home connection behind a generic cable or ADSL modem router that performs NAT translation (and it almost certainly does). Most of them have a USB port you can use to power up your Raspberry Pi, and if you’re only using the wifi functionality of the router, then it should have a free ethernet port for you to plug into. However, before we get to the point where we can set-and-forget your Raspberry Pi, we’ll need to set it up as a Tor relay node, for which you’ll need a keyboard and a monitor.
|
||||
|
||||
### The bootstrap script
|
||||
|
||||
I’ve adapted a popular Tor relay node bootstrap script for use with Raspbian Stretch -- you can find it in my GitHub repository here: <https://github.com/mricon/tor-relay-bootstrap-rpi>. Once you have booted up your Raspberry Pi and logged in with the default “pi” user, do the following:
|
||||
```
|
||||
sudo apt-get install -y git
|
||||
git clone https://github.com/mricon/tor-relay-bootstrap-rpi
|
||||
cd tor-relay-bootstrap-rpi
|
||||
sudo ./bootstrap.sh
|
||||
|
||||
```
|
||||
|
||||
Here is what the script will do:
|
||||
|
||||
1. Install the latest OS updates to make sure your Pi is fully patched
|
||||
|
||||
2. Configure your system for automated unattended updates, so you automatically receive security patches when they become available
|
||||
|
||||
3. Install Tor software
|
||||
|
||||
4. Tell your NAT router to forward the necessary ports to reach your relay (the ports we’ll use are 443 and 8080, since they are least likely to be filtered by your internet provider)
|
||||
|
||||
|
||||
|
||||
|
||||
Once the script is done, you’ll need to configure the torrc file -- but first, decide how much bandwidth you’ll want to donate to Tor traffic. First, type “[Speed Test][5]” into Google and click the “Run Speed Test” button. You can disregard the “Download speed” result, as your Tor relay can only operate as fast as your maximum upload bandwidth.
|
||||
|
||||
Therefore, take the “Mbps upload” number, divide by 8 and multiply by 1024 to find out the bandwidth speed in Kilobytes per second. E.g. if you got 21.5 Mbps for your upload speed, then that number is:
|
||||
```
|
||||
21.5 Mbps / 8 * 1024 = 2752 KBytes per second
|
||||
|
||||
```
|
||||
|
||||
You’ll want to limit your relay bandwidth to about half that amount, and allow bursting to about three-quarters of it. Once decided, open /etc/tor/torrc using your favourite editor and tweak the bandwidth settings.
|
||||
```
|
||||
RelayBandwidthRate 1300 KBytes
|
||||
RelayBandwidthBurst 2400 KBytes
|
||||
|
||||
```
|
||||
|
||||
Of course, if you’re feeling more generous, then feel free to put in higher numbers, though you don’t want to max out your outgoing bandwidth -- it will noticeably impact your day-to-day usage if these numbers are set too high.
|
||||
|
||||
While you have that file open, you should set two more things. First, the Nickname -- just for your own recordkeeping, and second the ContactInfo line, which should list a single email address. Since your relay will be running unattended, you should use an email address that you regularly check -- you will receive an alert from the “Tor Weather” service if your relay goes offline for longer than 48 hours.
|
||||
```
|
||||
Nickname myrpirelay
|
||||
ContactInfo you@example.com
|
||||
|
||||
```
|
||||
|
||||
Save the file and reboot the system to start the Tor relay.
|
||||
|
||||
### Testing to make sure Tor traffic is flowing
|
||||
|
||||
If you would like to make sure that the relay is functioning, you can run the “arm” tool:
|
||||
```
|
||||
sudo -u debian-tor arm
|
||||
|
||||
```
|
||||
|
||||
It will take a while to start, especially on older-generation boards, but eventually it will show you a bar chart of incoming and outgoing traffic (or error messages that will help you troubleshoot your setup).
|
||||
|
||||
Once you are convinced that everything is functioning, you can unplug the keyboard and the monitor and relocate the Raspberry Pi into the basement where it will quietly sit and shuffle encrypted bits around. Congratulations, you’ve helped improve privacy and combat malicious tracking online!
|
||||
|
||||
Learn more about Linux through the free ["Introduction to Linux" ][6] course from The Linux Foundation and edX.
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://www.linux.com/blog/intro-to-linux/2018/6/turn-your-raspberry-pi-tor-relay-node
|
||||
|
||||
作者：[Konstantin Ryabitsev][a]
|
||||
选题：[lujun9972](https://github.com/lujun9972)
|
||||
译者：[译者ID](https://github.com/译者ID)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]:https://www.linux.com/users/mricon
|
||||
[1]:https://www.torproject.org/
|
||||
[2]:https://en.wikipedia.org/wiki/Server_Name_Indication#Security_implications
|
||||
[3]:https://www.linux.com/blog/2017/10/tips-secure-your-network-wake-krack
|
||||
[4]:https://www.raspberrypi.org/downloads/raspbian/
|
||||
[5]:https://www.google.com/search?q=speed+test
|
||||
[6]:https://training.linuxfoundation.org/linux-courses/system-administration-training/introduction-to-linux
|
||||
@ -0,0 +1,73 @@
|
||||
7 open source tools to make literature reviews easy
|
||||
======
|
||||
|
||||
|
||||
|
||||
A good literature review is critical for academic research in any field, whether it is for a research article, a critical review for coursework, or a dissertation. In a recent article, I presented detailed steps for doing [a literature review using open source software][1].
|
||||
|
||||
The following is a brief summary of seven free and open source software tools described in that article that will make your next literature review much easier.
|
||||
|
||||
### 1\. GNU Linux
|
||||
|
||||
Most literature reviews are accomplished by graduate students working in research labs in universities. For absurd reasons, graduate students often have the worst computers on campus. They are often old, slow, and clunky Windows machines that have been discarded and recycled from the undergraduate computer labs. Installing a [flavor of GNU Linux][2] will breathe new life into these outdated PCs. There are more than [100 distributions][3], all of which can be downloaded and installed for free on computers. Most popular Linux distributions come with a "try-before-you-buy" feature. For example, with Ubuntu you can make a [bootable USB stick][4] that allows you to test-run the Ubuntu desktop experience without interfering in any way with your PC configuration. If you like the experience, you can use the stick to install Ubuntu on your machine permanently.
|
||||
|
||||
### 2\. Firefox
|
||||
|
||||
Linux distributions generally come with a free web browser, and the most popular is [Firefox][5]. Two Firefox plugins that are particularly useful for literature reviews are Unpaywall and Zotero. Keep reading to learn why.
|
||||
|
||||
### 3\. Unpaywall
|
||||
|
||||
Often one of the hardest parts of a literature review is gaining access to the papers you want to read for your review. The unintended consequence of copyright restrictions and paywalls is it has narrowed access to the peer-reviewed literature to the point that even [Harvard University is challenged][6] to pay for it. Fortunately, there are a lot of open access articles—about a third of the literature is free (and the percentage is growing). [Unpaywall][7] is a Firefox plugin that enables researchers to click a green tab on the side of the browser and skip the paywall on millions of peer-reviewed journal articles. This makes finding accessible copies of articles much faster that searching each database individually. Unpaywall is fast, free, and legal, as it accesses many of the open access sites that I covered in my paper on using [open source in lit reviews][8].
|
||||
|
||||
### 4\. Zotero
|
||||
|
||||
Formatting references is the most tedious of academic tasks. [Zotero][9] can save you from ever doing it again. It operates as an Android app, desktop program, and a Firefox plugin (which I recommend). It is a free, easy-to-use tool to help you collect, organize, cite, and share research. It replaces the functionality of proprietary packages such as RefWorks, Endnote, and Papers for zero cost. Zotero can auto-add bibliographic information directly from websites. In addition, it can scrape bibliographic data from PDF files. Notes can be easily added on each reference. Finally, and most importantly, it can import and export the bibliography databases in all publishers' various formats. With this feature, you can export bibliographic information to paste into a document editor for a paper or thesis—or even to a wiki for dynamic collaborative literature reviews (see tool #7 for more on the value of wikis in lit reviews).
|
||||
|
||||
### 5\. LibreOffice
|
||||
|
||||
Your thesis or academic article can be written conventionally with the free office suite [LibreOffice][10], which operates similarly to Microsoft's Office products but respects your freedom. Zotero has a word processor plugin to integrate directly with LibreOffice. LibreOffice is more than adequate for the vast majority of academic paper writing.
|
||||
|
||||
### 6\. LaTeX
|
||||
|
||||
If LibreOffice is not enough for your layout needs, you can take your paper writing one step further with [LaTeX][11], a high-quality typesetting system specifically designed for producing technical and scientific documentation. LaTeX is particularly useful if your writing has a lot of equations in it. Also, Zotero libraries can be directly exported to BibTeX files for use with LaTeX.
|
||||
|
||||
### 7\. MediaWiki
|
||||
|
||||
If you want to leverage the open source way to get help with your literature review, you can facilitate a [dynamic collaborative literature review][12]. A wiki is a website that allows anyone to add, delete, or revise content directly using a web browser. [MediaWiki][13] is free software that enables you to set up your own wikis.
|
||||
|
||||
Researchers can (in decreasing order of complexity): 1) set up their own research group wiki with MediaWiki, 2) utilize wikis already established at their universities (e.g., [Aalto University][14]), or 3) use wikis dedicated to areas that they research. For example, several university research groups that focus on sustainability (including [mine][15]) use [Appropedia][16], which is set up for collaborative solutions on sustainability, appropriate technology, poverty reduction, and permaculture.
|
||||
|
||||
Using a wiki makes it easy for anyone in the group to keep track of the status of and update literature reviews (both current and older or from other researchers). It also enables multiple members of the group to easily collaborate on a literature review asynchronously. Most importantly, it enables people outside the research group to help make a literature review more complete, accurate, and up-to-date.
|
||||
|
||||
### Wrapping up
|
||||
|
||||
Free and open source software can cover the entire lit review toolchain, meaning there's no need for anyone to use proprietary solutions. Do you use other libre tools for making literature reviews or other academic work easier? Please let us know your favorites in the comments.
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://opensource.com/article/18/6/open-source-literature-review-tools
|
||||
|
||||
作者：[Joshua Pearce][a]
|
||||
选题：[lujun9972](https://github.com/lujun9972)
|
||||
译者：[译者ID](https://github.com/译者ID)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]:https://opensource.com/users/jmpearce
|
||||
[1]:http://pareonline.net/getvn.asp?v=23&n=8
|
||||
[2]:https://opensource.com/article/18/1/new-linux-computers-classroom
|
||||
[3]:https://distrowatch.com/
|
||||
[4]:https://tutorials.ubuntu.com/tutorial/tutorial-create-a-usb-stick-on-windows#0
|
||||
[5]:https://www.mozilla.org/en-US/firefox/new/
|
||||
[6]:https://www.theguardian.com/science/2012/apr/24/harvard-university-journal-publishers-prices
|
||||
[7]:https://unpaywall.org/
|
||||
[8]:http://www.academia.edu/36709736/How_to_Perform_a_Literature_Review_with_Free_and_Open_Source_Software
|
||||
[9]:https://www.zotero.org/
|
||||
[10]:https://www.libreoffice.org/
|
||||
[11]:https://www.latex-project.org/
|
||||
[12]:https://www.academia.edu/1861756/Open_Source_Research_in_Sustainability
|
||||
[13]:https://www.mediawiki.org/wiki/MediaWiki
|
||||
[14]:http://wiki.aalto.fi
|
||||
[15]:http://www.appropedia.org/Category:MOST
|
||||
[16]:http://www.appropedia.org/Welcome_to_Appropedia
|
||||
108
sources/tech/20180612 What version of Linux am I running.md
Normal file
108
sources/tech/20180612 What version of Linux am I running.md
Normal file
@ -0,0 +1,108 @@
|
||||
What version of Linux am I running?
|
||||
======
|
||||
|
||||
|
||||
|
||||
The question "what version of Linux" can mean two different things. Strictly speaking, Linux is the kernel, so the question can refer specifically to the kernel's version number, or "Linux" can be used more colloquially to refer to the entire distribution, as in Fedora Linux or Ubuntu Linux.
|
||||
|
||||
`apt`, `dnf`, `yum`, or some other command to install packages.
|
||||
|
||||
Both are important, and you may need to know one or both answers to fix a problem with a system. For example, knowing the installed kernel version might help diagnose an issue with proprietary drivers, and identifying what distribution is running will help you quickly figure out if you should be using, or some other command to install packages.
|
||||
|
||||
The following will help you find out what version of the Linux kernel and/or what Linux distribution is running on a system.
|
||||
|
||||
### How to find the Linux kernel version
|
||||
|
||||
To find out what version of the Linux kernel is running, run the following command:
|
||||
```
|
||||
uname -srm
|
||||
|
||||
```
|
||||
|
||||
Alternatively, the command can be run by using the longer, more descriptive, versions of the various flags:
|
||||
```
|
||||
uname --kernel-name --kernel-release --machine
|
||||
|
||||
```
|
||||
|
||||
Either way, the output should look similar to the following:
|
||||
```
|
||||
Linux 4.16.10-300.fc28.x86_64 x86_64
|
||||
|
||||
```
|
||||
|
||||
This gives you (in order): the kernel name, the version of the kernel, and the type of hardware the kernel is running on. In this case, the kernel is Linux version 4.16.10-300.fc28.x86_64 running on an x86_64 system.
|
||||
|
||||
More information about the `uname` command can be found by running `man uname`.
|
||||
|
||||
### How to find the Linux distribution
|
||||
|
||||
There are several ways to figure out what distribution is running on a system, but the quickest way is the check the contents of the `/etc/os-release` file. This file provides information about a distribution including, but not limited to, the name of the distribution and its version number. The os-release file in some distributions contains more details than in others, but any distribution that includes an os-release file should provide a distribution's name and version.
|
||||
|
||||
To view the contents of the os-release file, run the following command:
|
||||
```
|
||||
cat /etc/os-release
|
||||
|
||||
```
|
||||
|
||||
On Fedora 28, the output looks like this:
|
||||
```
|
||||
NAME=Fedora
|
||||
|
||||
VERSION="28 (Workstation Edition)"
|
||||
|
||||
ID=fedora
|
||||
|
||||
VERSION_ID=28
|
||||
|
||||
PLATFORM_ID="platform:f28"
|
||||
|
||||
PRETTY_NAME="Fedora 28 (Workstation Edition)"
|
||||
|
||||
ANSI_COLOR="0;34"
|
||||
|
||||
CPE_NAME="cpe:/o:fedoraproject:fedora:28"
|
||||
|
||||
HOME_URL="https://fedoraproject.org/"
|
||||
|
||||
SUPPORT_URL="https://fedoraproject.org/wiki/Communicating_and_getting_help"
|
||||
|
||||
BUG_REPORT_URL="https://bugzilla.redhat.com/"
|
||||
|
||||
REDHAT_BUGZILLA_PRODUCT="Fedora"
|
||||
|
||||
REDHAT_BUGZILLA_PRODUCT_VERSION=28
|
||||
|
||||
REDHAT_SUPPORT_PRODUCT="Fedora"
|
||||
|
||||
REDHAT_SUPPORT_PRODUCT_VERSION=28
|
||||
|
||||
PRIVACY_POLICY_URL="https://fedoraproject.org/wiki/Legal:PrivacyPolicy"
|
||||
|
||||
VARIANT="Workstation Edition"
|
||||
|
||||
VARIANT_ID=workstation
|
||||
|
||||
```
|
||||
|
||||
As the example above shows, Fedora's os-release file provides the name of the distribution and the version, but it also identifies the installed variant (the "Workstation Edition"). If we ran the same command on Fedora 28 Server Edition, the contents of the os-release file would reflect that on the `VARIANT` and `VARIANT_ID` lines.
|
||||
|
||||
Sometimes it is useful to know if a distribution is like another, so the os-release file can contain an `ID_LIKE` line that identifies distributions the running distribution is based on or is similar to. For example, Red Hat Enterprise Linux's os-release file includes an `ID_LIKE` line stating that RHEL is like Fedora, and CentOS's os-release file states that CentOS is like RHEL and Fedora. The `ID_LIKE` line is very helpful if you are working with a distribution that is based on another distribution and need to find instructions to solve a problem.
|
||||
|
||||
CentOS's os-release file makes it clear that it is like RHEL, so documentation and questions and answers in various forums about RHEL should (in most cases) apply to CentOS. CentOS is designed to be a near clone of RHEL, so it is more compatible with its `LIKE` than some entries that might be found in the `ID_LIKE` field, but checking for answers about a "like" distribution is always a good idea if you cannot find the information you are seeking for the running distribution.
|
||||
|
||||
More information about the os-release file can be found by running `man os-release`.
|
||||
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://opensource.com/article/18/6/linux-version
|
||||
|
||||
作者：[Joshua Allen Holm][a]
|
||||
选题：[lujun9972](https://github.com/lujun9972)
|
||||
译者：[译者ID](https://github.com/译者ID)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]:https://opensource.com/users/holmja
|
||||
@ -0,0 +1,201 @@
|
||||
怎样在桌面上安装 Docker CE？
|
||||
=====
|
||||
|
||||
[在上一篇文章中][1]，我们学习了容器世界的一些基本术语。当我们运行命令并在后续文章中使用其中一些术语时，这些背景信息将会派上用场，包括这篇文章。本文将介绍在桌面 Linux, macOS 和 Windows 上安装 Docker，它适用于想要开始使用 Docker 容器的初学者。唯一的先决条件是你对命令行界面满意。
|
||||
|
||||
### 为什么我在本地机器上需要 Docker CE？
|
||||
|
||||
作为一个新用户，你很可能想知道为什么你在本地系统上需要容器。难道它们不是作为微服务在云和服务器中运行吗？尽管容器长期以来一直是 Linux 世界的一部分，但 Docker 使它们真正可以使用它的工具和技术。（to 校正者：这句话它们意义似乎不明确）
|
||||
|
||||
Docker 容器最大的优点是可以使用本地机器进行开发和测试。你在本地系统上创建的容器映像可以在“任何位置”运行。就应用程序在开发系统上运行良好但生产环境中出现问题这一点，开发人员和操作人员之间不会起冲突。
|
||||
|
||||
关键是，为了创建容器化的应用程序，你必须能够在本地系统上运行和创建容器。
|
||||
|
||||
你可以使用以下三个平台中的任何一个 -- 桌面 Linux, Windows 或 macOS 作为容器的开发平台。一旦 Docker 在这些系统上成功运行，你将可以在不同的平台上使用相同的命令。因此，接下来你运行的操作系统无关紧要。
|
||||
|
||||
这就是 Docker 之美。
|
||||
|
||||
### 让我们开始吧
|
||||
|
||||
现在有两个版本的 Docker：Docker 企业版（EE）和 Docker 社区版（CE）。我们将使用 Docker 社区版，这是一个免费的 Docker 版本，面向想要开始使用 Docker 的开发人员和爱好者。
|
||||
|
||||
Docker CE 有两个版本：stable 和 edge。顾名思义，stable（稳定）版本会为你提供经过充分测试的季度更新，而 edge 版本每个月都会提供新的更新。经过进一步的测试之后，这些边缘特征将被添加到稳定版本中。我建议新用户使用 stable 版本。
|
||||
|
||||
Docker CE 支持 macOS, Windows 10, Ubuntu 14.04, 16.04, 17.04 和 17.10，以及 Debian 7.7, 8, 9 和 10, Fedora 25, 26, 27 和 centOS。虽然你可以下载 Docker CE 二进制文件并安装到桌面 Linux 上，但我建议添加仓库源以便继续获得修补程序和更新。
|
||||
|
||||
### 在桌面 Linux 上安装 Docker CE
|
||||
|
||||
你不需要一个完整的桌面 Linux 来运行 Docker，你也可以将它安装在最小的 Linux 服务器上，即你可以在一个虚拟机中运行。在本教程中，我将在我的主系统 Fedora 27 和 Ubuntu 17.04 上运行它（to 校正者：这句话搞不清主要是什么系统）。
|
||||
|
||||
### 在 Ubuntu 上安装
|
||||
|
||||
首先，运行系统更新，以便你的 Ubuntu 软件包完全更新：
|
||||
```
|
||||
$ sudo apt-get update
|
||||
|
||||
```
|
||||
|
||||
现在运行系统升级：
|
||||
```
|
||||
$ sudo apt-get dist-upgrade
|
||||
|
||||
```
|
||||
|
||||
然后安装 Docker PGP 密钥：
|
||||
```
|
||||
sudo add-apt-repository "deb [arch=amd64] https://download.docker.com/linux/ubuntu $(lsb_release -cs) stable"
|
||||
|
||||
Update the repository info again:
|
||||
$ sudo apt-get update
|
||||
|
||||
```
|
||||
|
||||
现在安装 Docker CE：
|
||||
```
|
||||
$ sudo apt-get install docker-ce
|
||||
|
||||
```
|
||||
|
||||
一旦安装，Docker CE 就会在基于 Ubuntu 的系统上自动运行，让我们来检查它是否在运行：
|
||||
```
|
||||
$ sudo systemctl status docker
|
||||
|
||||
```
|
||||
|
||||
你应该得到以下输出：
|
||||
```
|
||||
docker.service - Docker Application Container Engine
|
||||
Loaded: loaded (/lib/systemd/system/docker.service; enabled; vendor preset: enabled)
|
||||
Active: active (running) since Thu 2017-12-28 15:06:35 EST; 19min ago
|
||||
Docs: https://docs.docker.com
|
||||
Main PID: 30539 (dockerd)
|
||||
|
||||
```
|
||||
|
||||
由于 Docker 安装在你的系统上，你现在可以使用 Docker CLI（命令行界面）运行 Docker 命令。像往常一样，我们运行 ‘Hello World’ 命令：
|
||||
```
|
||||
$ sudo docker run hello-world
|
||||
|
||||
```
|
||||
|
||||
![YMChR_7xglpYBT91rtXnqQc6R1Hx9qMX_iO99vL8][2]
|
||||
恭喜！在你的 Ubuntu 系统上正在运行着 Docker。
|
||||
|
||||
### 在 Fedora 上安装 Docker CE
|
||||
|
||||
Fedora 27 上的情况有些不同。在 Fedora 上，你首先需要安装 def-plugins-core 包，这将允许你从 CLI 管理你的 DNF 包。
|
||||
```
|
||||
$ sudo dnf -y install dnf-plugins-core
|
||||
|
||||
```
|
||||
|
||||
现在在你的系统上安装 Docker 仓库：
|
||||
```
|
||||
$ sudo dnf config-manager \
|
||||
--add-repo \
|
||||
https://download.docker.com/linux/fedora/docker-ce.repo
|
||||
It’s time to install Docker CE:
|
||||
|
||||
$ sudo dnf install docker-ce
|
||||
|
||||
```
|
||||
|
||||
与 Ubuntu 不同，Docker 不会在 Fedora 上自动启动。那么让我们启动它：
|
||||
```
|
||||
$ sudo systemctl start docker
|
||||
|
||||
```
|
||||
|
||||
你必须在每次重新启动后手动启动 Docker，因此让我们将其配置为在重新启动后自动启动。$ systemctl enable docker 就行。现在该运行 Hello World 命令了：
|
||||
```
|
||||
$ sudo docker run hello-world
|
||||
|
||||
```
|
||||
|
||||
恭喜，在你的 Fedora 27 系统上正在运行着 Docker。
|
||||
|
||||
### 解除 root
|
||||
|
||||
你可能已经注意到你必须使用 sudo 来运行 Docker 命令。这是因为 Docker 守护进程与 UNIX 套接字绑定，而不是 TCP 端口，套接字由 root 用户拥有。所以，你需要 sudo 权限才能运行 docker 命令。你可以将系统用户添加到 docker 组，这样它就不需要 sudo 了：
|
||||
```
|
||||
$ sudo groupadd docker
|
||||
|
||||
```
|
||||
|
||||
在大多数情况下，在安装 Docker CE 时会自动创建 Docker 用户组，因此你只需将用户添加到该组中即可：
|
||||
```
|
||||
$ sudo usermod -aG docker $USER
|
||||
|
||||
```
|
||||
|
||||
为了测试组是否已经成功添加，根据用户名运行 groups 命令：
|
||||
```
|
||||
$ groups swapnil
|
||||
|
||||
```
|
||||
|
||||
（这里，swapnil 是用户名。）
|
||||
|
||||
这是在我系统上的输出：
|
||||
```
|
||||
$ swapnil : swapnil adm cdrom sudo dip plugdev lpadmin sambashare docker
|
||||
|
||||
```
|
||||
|
||||
你可以看到该用户也属于 docker 组。注销系统，这样组就会生效。一旦你再次登录，在不使用 sudo 的情况下试试 Hello World 命令：
|
||||
```
|
||||
$ docker run hello-world
|
||||
|
||||
```
|
||||
|
||||
你可以通过运行以下命令来查看关于 Docker 的安装版本以及更多系统信息：
|
||||
```
|
||||
$ docker info
|
||||
|
||||
```
|
||||
|
||||
### 在 macOS 和 Windows 上安装 Docker CE
|
||||
|
||||
你可以在 macOS 和 Windows 上很轻松地安装 Docker CE（和 EE）。下载官方为 macOS 提供的 Docker 安装包，在 macOS 上安装应用程序的方式是只需将它们拖到 Applications 目录即可。一旦文件被复制，从 spotlight（译者注：mac 下的搜索）下打开 Docker 开始安装。一旦安装，Docker 将自动启动，你可以在 macOS 的顶部看到它。
|
||||
|
||||
![IEX23j65zYlF8mZ1c-T_vFw_i1B1T1hibw_AuhEA][3]
|
||||
|
||||
macOS 是类 UNIX，所以你可以简单地打开终端应用程序，并开始使用 Docker 命令。测试 hello world 应用：
|
||||
```
|
||||
$ docker run hello-world
|
||||
|
||||
```
|
||||
|
||||
恭喜，你已经在你的 macOS 上运行了 Docker。
|
||||
|
||||
### 在 Windows 10 上安装 Docker
|
||||
|
||||
你需要最新版本的 Windows 10 Pro 或 Server 才能在它上面安装或运行 Docker。如果你没有完全更新，Windows 将不会安装 Docker。我在 Windows 10 系统上遇到了错误，必须运行系统更新。我的版本还很落后，我出现了[这个][14] bug。所以，如果你无法在 Windows 上安装 Docker，只要知道并不是只有你一个。仔细检查该 bug 以找到解决方案。
|
||||
|
||||
一旦你在 Windows 上安装 Docker 后，你可以通过 WSL 使用 bash shell，或者使用 PowerShell 来运行 Docker 命令。让我们在 PowerShell 中测试 “Hello World” 命令：
|
||||
```
|
||||
PS C:\Users\swapnil> docker run hello-world
|
||||
|
||||
```
|
||||
|
||||
恭喜，你已经在 Windows 上运行了 Docker。
|
||||
|
||||
在下一篇文章中，我们将讨论如何从 DockerHub 中拉取镜像并在我们的系统上运行容器。我们还会讨论推送我们自己的容器到 Docker Hub。
|
||||
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://www.linux.com/blog/learn/intro-to-linux/how-install-docker-ce-your-desktop
|
||||
|
||||
作者：[SWAPNIL BHARTIYA][a]
|
||||
译者：[MjSeven](https://github.com/MjSeven)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
选题：[lujun9972](https://github.com/lujun9972)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]:https://www.linux.com/users/arnieswap
|
||||
[1]:https://www.linux.com/blog/intro-to-linux/2017/12/container-basics-terms-you-need-know
|
||||
[2]:https://lh5.googleusercontent.com/YMChR_7xglpYBT91rtXnqQc6R1Hx9qMX_iO99vL8Z8C0-BlynDcL5B5pG-zzH0fKU0Qvnzd89v0KDEbZiO0gTfGNGfDtO-FkTt0bmzIQ-TKbNmv18S9RXdkSeXqgKDFRewnaHPj2
|
||||
[3]:https://lh3.googleusercontent.com/IEX23j65zYlF8mZ1c-T_vFw_i1B1T1hibw_AuhEAfwv9oFpMfcAqkgEk7K5o58iDAAfGozSpIvY_qEsTOHRlSbesMKwTnG9rRkWba1KPSmnuH1LyoccDGNO3Clbz8du0gSByZxNj
|
||||
[4]:https://github.com/docker/for-win/issues/1263
|
||||
@ -1,100 +0,0 @@
|
||||
底层 Linux 容器运行时的发展史
|
||||
======
|
||||
|
||||
|
||||
|
||||
在 Red Hat，我们乐意这么说，“容器就是 Linux，Linux 就是容器”。下面解释一下这种说法。传统的容器是操作系统中的进程，通常具有如下 3 个特性：
|
||||
|
||||
### 1\. 资源限制
|
||||
|
||||
当你在系统中运行多个容器时，你肯定不希望某个容器独占系统资源，所以我们需要使用资源约束来控制 CPU、内存和网络带宽等资源。Linux 内核提供了 cgroups 特性，可以通过配置控制容器进程的资源使用。
|
||||
|
||||
### 2\. 安全性配置
|
||||
|
||||
一般而言，你不希望你的容器可以攻击其它容器或甚至攻击的你的主机系统。我们使用了 Linux 内核的若干特性建立安全隔离，相关特性包括 SELinux、seccomp 和 capabilities。
|
||||
|
||||
（LCTT 译注：从 2.2 版本内核开始，Linux 将特权从超级用户中分离，产生了一系列可以单独启用或关闭的 capabilities）
|
||||
|
||||
### 3\. 虚拟隔离
|
||||
|
||||
容器外的任何进程对于容器而言都应该不可见。容器应该使用独立的网络。不同的容器对应的进程都应该可以绑定 80 端口。每个容器的<ruby>内核映像<rt>image</rt></ruby>、<ruby>根文件系统<rt>rootfs</rt>都应该相互独立。在 Linux 中，我们使用内核 namespaces 特性提供<ruby>虚拟隔离<rt>virtual separation</rt></ruby>。
|
||||
|
||||
那么，具有安全性配置并且在 cgroup 和 namespace 下运行的进程都可以称为容器。查看一下 Red Hat Enterprise Linux 7 操作系统中的 PID 1 的进程 systemd，你会发现 systemd 运行在一个 cgroup 下。
|
||||
```
|
||||
# tail -1 /proc/1/cgroup
|
||||
1:name=systemd:/
|
||||
```
|
||||
`ps` 命令让我们看到 systemd 进程具有 SELinux 标签：
|
||||
```
|
||||
# ps -eZ | grep systemd
|
||||
system_u:system_r:init_t:s0 1 ? 00:00:48 systemd
|
||||
```
|
||||
|
||||
以及 capabilities：
|
||||
```
|
||||
# grep Cap /proc/1/status
|
||||
...
|
||||
CapEff: 0000001fffffffff
|
||||
CapBnd: 0000001fffffffff
|
||||
CapBnd: 0000003fffffffff
|
||||
```
|
||||
|
||||
最后，查看 `/proc/1/ns` 子目录，你会发现 systemd 运行所在的 namespace。
|
||||
```
|
||||
ls -l /proc/1/ns
|
||||
lrwxrwxrwx. 1 root root 0 Jan 11 11:46 mnt -> mnt:[4026531840]
|
||||
lrwxrwxrwx. 1 root root 0 Jan 11 11:46 net -> net:[4026532009]
|
||||
lrwxrwxrwx. 1 root root 0 Jan 11 11:46 pid -> pid:[4026531836]
|
||||
...
|
||||
```
|
||||
|
||||
如果 PID 1 进程（实际上每个系统进程）具有资源约束、安全性配置和 namespace，那么我想说系统上的每一个进程都运行在容器中。
|
||||
|
||||
容器运行时工具也不过是修改了资源约束、安全性配置和 namespace，然后 Linux 内核运行起进程。容器启动后，容器运行时可以在容器内监控 PID 1 进程，也可以监控容器的标准输入输出，从而进行容器进程的生命周期管理。
|
||||
|
||||
### 容器运行时
|
||||
|
||||
你可能自言自语道，“哦，systemd 看起来很像一个容器运行时”。经过若干次关于“为何容器运行时不使用 `systemd-nspawn` 工具启动容器”的邮件讨论后，我认为值得讨论一下容器运行时及其发展史。
|
||||
|
||||
[Docker][1] 通常被称为容器运行时，但“容器运行时”是一个被过度使用的词语。当用户提到“容器运行时”，他们其实提到的是为开发人员提供便利的<ruby>上层<rt>high-level</rt></ruby>工具，包括 Docker，[CRI-O][2] 和 [RKT][3]。这些工具都是基于 API 的，涉及操作包括从容器仓库拉取容器镜像、配置存储和启动容器等。启动容器通常涉及一个特殊工具，用于配置内核如何运行容器，这类工具也被称为“容器运行时”，下文中我将称其为“底层容器运行时”以作区分。像 Docker、CRI-O 这样的守护进程及形如 [Podman][4]、[Buildah][5] 的命令行工具，似乎更应该被称为“容器管理器”。
|
||||
|
||||
早期版本的 Docker 使用 `lxc` 工具集启动容器，该工具出现在 `systemd-nspawn` 之前。Red Hat 最初试图将 `[libvirt][6]` (`libvirt-lxc`) 集成到 Docker 中替代 `lxc` 工具，因为 RHEL 并不支持 `lxc`。`libvirt-lxc` 也没有使用 `systemd-nspawn`，在那时 systemd 团队仅将 `systemd-nspawn` 视为测试工具，不适用于生产环境。
|
||||
|
||||
与此同时，包括我 Red Hat 团队部分成员在内的<ruby>上游<rt>upstream</rt></ruby> Docker 开发者，认为应该采用 golang 原生的方式启动容器，而不是调用外部应用。他们的工作促成了 libcontainer 这个 golang 原生库，用于启动容器。Red Hat 工程师更看好该库的发展前景，放弃了 `libvirt-lxc`。
|
||||
|
||||
后来成立 [<ruby>开放容器组织<rt>Open Container Initiative</rt></ruby>][7] (OCI) 的部分原因就是人们希望用其它方式启动容器。传统的基于 namespaces 隔离的容器已经家喻户晓，但人们也有<ruby>虚拟机级别隔离<rt>virtual machine-level isolation</rt></ruby>的需求。Intel 和 [Hyper.sh][8] 正致力于开发基于 KVM 隔离的容器，Microsoft 致力于开发基于 Windows 的容器。OCI 希望有一份定义容器的标准规范，因而产生了 [OCI <ruby>运行时规范<rt>Runtime Specification</rt></ruby>][9]。
|
||||
|
||||
OCI 运行时规范定义了一个 JSON 文件格式，用于描述要运行的二进制，如何容器化以及容器根文件系统的位置。一些工具用于生成符合标准规范的 JSON 文件，另外的工具用于解析 JSON 文件并在根文件系统上运行容器。Docker 的部分代码被抽取出来构成了 libcontainer 项目，该项目被贡献给 OCI。上游 Docker 工程师及我们自己的工程师创建了一个新的前端工具，用于解析符合 OCI 运行时规范的 JSON 文件，然后与 libcontainer 交互以便启动容器。这个前端工具就是 `[runc][10]`，也被贡献给 OCI。虽然 `runc` 可以解析 OCI JSON 文件，但用户需要自行生成这些文件。此后，`runc` 也成为了最流行的底层容器运行时，基本所有的容器管理工具都支持 `runc`，包括 CRI-O，Docker，Buildah，Podman 和 [Cloud Foundry Garden][11] 等。此后，其它工具的实现也参照 OCI 运行时规范，以便可以运行 OCI 兼容的容器。
|
||||
|
||||
[Clear Containers][12] 和 Hyper.sh 的 `runV` 工具都是参照 OCI 运行时规范运行基于 KVM 的容器，二者将其各自工作合并到一个名为 [Kata][12] 的新项目中。在去年，Oracle 创建了一个示例版本的 OCI 运行时工具，名为 [RailCar][13]，使用 Rust 语言编写。但该 GitHub 项目已经两个月没有更新了，故无法判断是否仍在开发。几年前，Vincent Batts 试图创建一个名为 `[nspawn-oci][14]` 的工具，用于解析 OCI 运行时规范文件并启动 `systemd-nspawn`；但似乎没有引起大家的注意，而且也不是原生的实现。
|
||||
|
||||
如果有开发者希望实现一个原生的 `systemd-nspawn --oci OCI-SPEC.json` 并让 systemd 团队认可和提供支持，那么CRI-O，Docker 和 Podman 等容器管理工具将可以像使用 `runc` 和 Clear Container/runV ([Kata][15]) 那样使用这个新的底层运行时。（目前我的团队没有人参与这方面的工作。）
|
||||
|
||||
总结如下，在 3-4 年前，上游开发者打算编写一个底层的 golong 工具用于启动容器，最终这个工具就是 `runc`。那时开发者使用 C 编写的 `lxc` 工具，在 `runc` 开发后，他们很快转向 `runc`。我很确信，当决定构建 libcontainer 时，他们对 `systemd-nspawn` 或其它非原生（即不使用 golong）的运行 namespaces 隔离的容器的方式都不感兴趣。
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://opensource.com/article/18/1/history-low-level-container-runtimes
|
||||
|
||||
作者：[Daniel Walsh][a]
|
||||
译者：[pinewall](https://github.com/pinewall)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]:https://opensource.com/users/rhatdan
|
||||
[1]:https://github.com/docker
|
||||
[2]:https://github.com/kubernetes-incubator/cri-o
|
||||
[3]:https://github.com/rkt/rkt
|
||||
[4]:https://github.com/projectatomic/libpod/tree/master/cmd/podman
|
||||
[5]:https://github.com/projectatomic/buildah
|
||||
[6]:https://libvirt.org/
|
||||
[7]:https://www.opencontainers.org/
|
||||
[8]:https://www.hyper.sh/
|
||||
[9]:https://github.com/opencontainers/runtime-spec
|
||||
[10]:https://github.com/opencontainers/runc
|
||||
[11]:https://github.com/cloudfoundry/garden
|
||||
[12]:https://clearlinux.org/containers
|
||||
[13]:https://github.com/oracle/railcar
|
||||
[14]:https://github.com/vbatts/nspawn-oci
|
||||
[15]:https://github.com/kata-containers
|
||||
257
translated/tech/20180418 The Linux Filesystem Explained.md
Normal file
257
translated/tech/20180418 The Linux Filesystem Explained.md
Normal file
@ -0,0 +1,257 @@
|
||||
# Linux文件系统详解
|
||||
|
||||
|
||||
|
||||
早在1996年，在真正理解文件系统的结构之前，我就学会了如何在我崭新的 Linux 上安装软件。这是一个问题，但不是程序的问题，因为即使我不知道实际的可执行文件在哪里，它们也会神奇地工作。问题在于文档。
|
||||
|
||||
你看，那时候，Linux 不是像今天这样直观，用户友好的系统。 你必须读很多东西。 你必须知道你的 CRT 显示器的频率以及拨号调制解调器的噪音来龙去脉，以及其他数以百计的事情。 我很快就意识到我需要花一些时间来掌握目录的组织方式以及 /etc（不用于其他文件），/usr（不是用于用户文件）和 /*bin *（ 不是垃圾桶）的意思。
|
||||
|
||||
本教程将帮助您加快速度，比我做得更快。
|
||||
|
||||
### 结构
|
||||
|
||||
从终端窗口探索 Linux 文件系统是有道理的，这并不是因为作者是一个脾气暴躁的老人，并且对新孩子和他们漂亮的图形工具不以为然——尽管有一些事实——但是因为终端，尽管是文本——只有更好的工具才能显示 Linux 目录树的结构。
|
||||
|
||||
事实上，这是您将安装的第一个工具的名称：*tree*。如果你正在使用 Ubuntu 或 Debian ，你可以：
|
||||
|
||||
```
|
||||
sudo apt install tree
|
||||
|
||||
```
|
||||
|
||||
在 Red Hat 或 Fedora :
|
||||
|
||||
```
|
||||
sudo dnf install tree
|
||||
|
||||
```
|
||||
|
||||
对于 SUSE/openSUSE 可以使用 `zypper`：
|
||||
|
||||
```
|
||||
sudo zypper install tree
|
||||
|
||||
```
|
||||
|
||||
对于使用 Arch （Manjaro，Antergos，等等）使用：
|
||||
|
||||
```
|
||||
sudo pacman -S tree
|
||||
|
||||
```
|
||||
|
||||
...等等。
|
||||
|
||||
一旦安装好，在终端窗口运行 *tree* 命令：
|
||||
|
||||
```
|
||||
tree /
|
||||
|
||||
```
|
||||
|
||||
上述指令中的 `/` 指的是根目录。系统中的其他目录都是从根目录分支而出，当你运行 `tree` 命令，并且告诉它从根目录开始，那么你就可以看到整个目录树，系统中的所有目录及其子目录，还有他们的文件。
|
||||
|
||||
如果您已经使用您的系统有一段时间了，这可能需要一段时间，因为即使您自己还没有生成很多文件，Linux系统及其应用程序总是记录、缓存和存储临时文件。文件系统中的条目数量可以快速增长。
|
||||
|
||||
不过，不要感到不知所措。 相反，试试这个：
|
||||
|
||||
```
|
||||
tree -L 1 /
|
||||
|
||||
```
|
||||
|
||||
您应该看到如图 1 所示。
|
||||
|
||||
|
||||
|
||||
上面的指令可以翻译为“只显示以 /（根目录） 开头的目录树的第一级”。 `-L` 选项告诉树你想看到多少层目录。
|
||||
|
||||
大多数 Linux 发行版都会向您显示与您在上图中看到的相同或非常类似的结构。 这意味着，即使你现在感到困惑，掌握这一点，你将掌握大部分（如果不是全部的话）整个世界的 Linux 文件系统。
|
||||
|
||||
为了让您开始走上掌握之路，让我们看看每个目录的用途。 当我们查看每一个目录的时候，你可以使用 *ls* 来查看他们的内容。
|
||||
|
||||
### 目录
|
||||
|
||||
从上到下，你所看到的目录如下
|
||||
|
||||
#### _/bin_
|
||||
|
||||
*/bin* 目录是包含一些二进制文件的目录，即可以运行的一些应用程序。 你会在这个目录中找到上面提到的 *ls* 程序，以及用于新建和删除文件和目录，移动它们基本工具。还有其他一些程序，等等， 文件系统树的其他部分有更多的 *bin* 目录，但我们将在一分钟内讨论这些目录。
|
||||
|
||||
#### _/boot_
|
||||
|
||||
*/boot* 目录包含启动系统所需的文件。 我必须要说吗？ 好吧，我会说：**不要动它**！ 如果你在这里弄乱了其中一个文件，你可能无法运行你的 Linux，修复破坏的系统是非常痛苦的一件事。 另一方面，不要太担心无意中破坏系统：您必须拥有超级用户权限才能执行此操作。
|
||||
|
||||
#### _/dev_
|
||||
|
||||
*/dev* 目录包含设备文件。 其中许多是在启动时或甚至在运行时生成的。 例如，如果您将新的网络摄像头或 USB 随身碟连接到您的机器中，则会自动弹出一个新的设备条目。
|
||||
|
||||
#### _/etc_
|
||||
|
||||
*/etc* 的目录名称会让人变得非常的困惑。*/etc* 从最早的 Unixes 系统中得到它的名称，它的字面意思是 “et cetera” ，因为它是系统文件管理员不确定在哪里放置文件的垃圾场。
|
||||
|
||||
现在，说 */etc* 是“要配置的所有内容”更为恰当，因为它包含大部分（如果不是全部的话）系统配置文件。 例如，包含系统名称，用户及其密码，网络上计算机名称以及硬盘上分区的安装位置和时间的文件都在这里。 再说一遍，如果你是 Linux 的新手，最好是不要在这里接触太多，直到你对系统的工作有更好的理解。
|
||||
|
||||
#### _/home_
|
||||
|
||||
*/home* 是您可以找到用户个人目录的地方。 在我的情况下，*/home* 下有两个目录：*/home/paul*，其中包含我所有的东西；另外一个目录是 */home/guest* 目录，以防有人需要使用我的电脑。
|
||||
|
||||
#### _/lib_
|
||||
|
||||
*/lib* 是库文件所在的地方。 库是包含应用程序可以使用的代码文件。 它们包含应用程序用于在桌面上绘制窗口，控制外围设备或将文件发送到硬盘的代码片段。
|
||||
|
||||
在文件系统周围散布着更多的 *lib* 目录，但是这个直接挂载在 / 的 */lib* 目录是特殊的，除此之外，它包含了所有重要的内核模块。 内核模块是使您的视频卡，声卡，WiFi，打印机等工作的驱动程序。
|
||||
|
||||
#### _/media_
|
||||
|
||||
在 */media* 目录中，当您插入外部存储并试图访问它时，将自动挂载它。与此列表中的大多数其他项目不同，*/media* 并不追溯到 1970 年代，主要是因为当计算机正在运行而动态地插入和检测存储（ U 盘, USB 硬盘，SD卡，外部 SSD 等)，这是最近才发生的事。
|
||||
|
||||
#### _/mnt_
|
||||
|
||||
然而，*/mnt* 目录是一些过去的残余。这是您手动挂载存储设备或分区的地方。现在不常用了。
|
||||
|
||||
#### _/opt_
|
||||
|
||||
*/opt* 目录通常是您编译软件（即，您从源代码构建，并不是从您的系统的软件库中安装软件）的地方。应用程序最终会出现在 */opt/bin* 目录，库会在 */opt/lib* 目录中出现。
|
||||
|
||||
稍微的题外话：应用程序和库的另一个地方是 */usr/local*，在这里安装软件时，也会有 */usr/local/bin* 和 */usr/local/lib* 目录。开发人员如何配置文件来控制编译和安装过程，这就决定了软件安装到哪个地方。
|
||||
|
||||
#### _/proc_
|
||||
|
||||
*/proc*，就像 */dev* 是一个虚拟目录。它包含有关您的计算机的信息，例如关于您的 CPU 和您的 Linux 系统正在运行的内核的信息。与 */dev* 一样，文件和目录是在计算机启动或运行时生成的，因为您的系统正在运行且会发生变化。
|
||||
|
||||
#### _/root_
|
||||
|
||||
*/root* 是系统的超级用户（也称为“管理员”）的主目录。 它与其他用户的主目录是分开的，因为您打算去动它。 所以把自己的东西放在你自己的目录中，伙计们。
|
||||
|
||||
#### _/run_
|
||||
|
||||
*/run* 是另一个新目录。系统进程出于自己的邪恶原因使用它来存储临时数据。这是另一个不要动它的文件夹例子。
|
||||
|
||||
#### _/sbin_
|
||||
|
||||
*/sbin* 与 */bin* 类似，但它包含的应用程序只有超级用户（即首字母的 s ）才需要。您可以使用 `sudo` 命令使用这些应用程序，该命令暂时允许您在许多发行版上拥有超级用户权限。*/sbin* 目录通常包含可以安装、删除和格式化内容的工具。你可以想象，如果你使用不当，这些指令中有一些是致命的，所以要小心处理。
|
||||
|
||||
#### _/usr_
|
||||
|
||||
*/usr* 目录是在 UNIX 早期用户的主目录被保留的地方。然而，正如我们上面看到的，现在 */home* 是用户保存他们的东西的地方。如今，*/usr* 包含了大量目录，而这些目录又包含了应用程序、库、文档、壁纸、图标和许多其他需要应用程序和服务共享的内容。
|
||||
|
||||
您还可以在 */usr* 目录下找到 */bin*，*/sbin*，*/lib* 目录，他们与挂载到根目录下的那些有什么区别呢？现在的区别不是很大。在早期，/bin 目录（挂载在根目录下的）只会包含一些基本的命令，例如 *ls*，*mv* 和 *rm* ；这是一些在安装系统的时候就会预装的一些命令，用于维护系统的一个基本的命令。 而 */usr/bin* 目录则包含了用户自己安装和用于工作的软件，例如文字处理器，浏览器和一些其他的软件。
|
||||
|
||||
但是许多现代的 Linux 发行版只是把所有的东西都放到 */usr/bin* 中，并让 */bin* 指向 */usr/bin*，以防彻底删除它会破坏某些东西。因此，Debian、Ubuntu 和 Mint 仍然保持 */bin* 和 */usr/bin* （和 */sbin* 和 */usr/sbin* ）分离；其他的，比如 Arch 和它衍生版，只是有一个二进制的“真实”目录，*/usr/bin*，其余的或 *bin 是指向 */usr/ bin* 的“假”目录。
|
||||
|
||||
#### _/srv_
|
||||
|
||||
*/srv* 目录包含服务器的数据。 如果您正在 Linux 机器上运行 Web 服务器，您网站的 HTML文件将放到 */srv/http*（或 */srv/www*）。 如果您正在运行 FTP 服务器，则您的文件将放到 */srv/ftp*。
|
||||
|
||||
#### _/sys_
|
||||
|
||||
*/sys* 是另一个类似 */proc* 和 */dev* 的虚拟目录，它还包含连接到计算机的设备的信息。
|
||||
|
||||
在某些情况下，您还可以操纵这些设备。 例如，我可以通过修改存储在 /sys/devices/pci0000:00/0000:00:02.0/drm/card1/card1-eDP-1/intel_backlight/brightness 中的值来更改笔记本电脑屏幕的亮度（在你的机器上你可能会有不同的文件）。但要做到这一点，你必须成为超级用户。原因是，与许多其他虚拟目录一样，在 */sys* 中打乱内容和文件可能是危险的，您可能会破坏系统。直到你确信你知道你在做什么。否则不要动它。
|
||||
|
||||
#### _/tmp_
|
||||
|
||||
*/tmp* 包含临时文件，通常由正在运行的应用程序放置。文件和目录通常（并非总是）包含应用程序现在不需要但以后可能需要的数据。为了释放内存，它被存储在这里。
|
||||
|
||||
您还可以使用 */tmp* 来存储您自己的临时文件—— /tmp 是挂载到根目录下您可以在不成为超级用户的情况下与它进行实际交互少数目录之一。问题是，应用程序有时不会回来检索和删除文件和目录，而且 */tmp* 常常会耗尽硬盘上的空间，使其塞满垃圾。在本系列的后面，我们将看到如何清理它。
|
||||
|
||||
#### _/var_
|
||||
|
||||
*/var* 最初被命名是因为它的内容被认为是可变的，因为它经常变化。今天，它有点用词不当，因为还有许多其他目录也包含频繁更改的数据，特别是我们上面看到的虚拟目录。
|
||||
|
||||
不管怎样，*/var* 目录包含了类似 */var/log* 子目录的日志文件。日志是记录系统中发生的事件的文件。如果内核中出现了什么问题，它将被记录到 */var/log* 文件中；如果有人试图从外部侵入您的计算机，您的防火墙也将记录尝试。它还包含用于任务的假脱机程序。这些“任务”可以是您在不得不等待时发送给共享打印机的任务，因为另一个用户正在打印一个长文档，或者是等待发送给系统上的用户的邮件。
|
||||
|
||||
您的系统可能还有一些我们上面没有提到的目录。例如，在屏幕截图中，有一个 */snap* 目录。这是因为这张截图是在Ubuntu系统上截取的。Ubuntu 最近将 [snap][1] 包作为一种分发软件的方式。*/snap* 目录包含所有文件和从 snaps 安装的软件。
|
||||
|
||||
### 更深入的研究
|
||||
|
||||
这里仅仅谈了根目录，但是许多子目录都指向它们自己的一组文件和子目录。图 2 给出了基本文件系统的总体概念（图片是在 Paul Gardner 的 CC BY-SA 许可下提供的），[Wikipedia 对每个目录的用途进行了总结][2]。
|
||||
|
||||
|
||||
![filesystem][4]
|
||||
|
||||
图 2：标准 Unix 文件系统
|
||||
|
||||
[许可][5]
|
||||
|
||||
Paul Gardner
|
||||
|
||||
要自行探索文件系统，请使用 `cd` 命令:
|
||||
|
||||
```
|
||||
cd
|
||||
|
||||
```
|
||||
|
||||
将带您到您所选择的目录（ *cd* 代表更改目录）。
|
||||
|
||||
如果你不知道你在哪儿，
|
||||
|
||||
```
|
||||
pwd
|
||||
|
||||
```
|
||||
|
||||
*pwd* 会告诉你，你到底在哪里，（ *pwd* 代表打印工作目录 ），同时
|
||||
|
||||
```
|
||||
cd
|
||||
|
||||
```
|
||||
|
||||
*cd* 命令在没有任何选项或者参数的时候，将会直接带你到你自己的主目录，这是一个安全舒适的地方。
|
||||
|
||||
最后，
|
||||
|
||||
```
|
||||
cd ..
|
||||
|
||||
```
|
||||
|
||||
*cd ..* 将会带你到上一层目录，会使你更加接近根目录，如果你在 */usr/share/wallpapers* 目录，然后你执行 `cd ..` 命令，你将会跳转到 `/usr/share` 目录
|
||||
|
||||
要查看目录里有什么内容，使用
|
||||
|
||||
```
|
||||
ls
|
||||
|
||||
```
|
||||
|
||||
或这简单的使用
|
||||
|
||||
```
|
||||
l
|
||||
|
||||
```
|
||||
|
||||
列出你所在目录的内容。
|
||||
|
||||
当然，您总是可以使用 `tree` 来获得目录中内容的概述。在 */usr/share* 上试试——里面有很多有趣的东西。
|
||||
|
||||
### 总结
|
||||
|
||||
尽管 Linux 发行版之间存在细微差别，但它们的文件系统的布局非常相似。 你可以这么说：一旦你认识一个，你就会知道他们。 知道文件系统的最好方法就是探索它。 因此，伴随 `tree` ，`ls` 和 `cd` 进入未知的领域吧。
|
||||
|
||||
您不能仅仅通过查看文件系统就破坏文件系统，因此请从一个目录移动到另一个目录并进行浏览。 很快你就会发现 Linux 文件系统及其布局的确很有意义，并且你会直观地知道在哪里可以找到应用程序，文档和其他资源。
|
||||
|
||||
通过 Linux 基金会和 edX 免费的 “[Linux入门][6]” 课程了解更多有关 Linux 的信息。
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://www.linux.com/blog/learn/intro-to-linux/2018/4/linux-filesystem-explained
|
||||
|
||||
作者：[PAUL BROWN][a]
|
||||
选题：[lujun9972](https://github.com/lujun9972)
|
||||
译者：[amwps290](https://github.com/amwps290)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]:https://www.linux.com/users/bro66
|
||||
[1]:https://www.ubuntu.com/desktop/snappy
|
||||
[2]:https://en.wikipedia.org/wiki/Unix_filesystem#Conventional_directory_layout
|
||||
[3]:https://www.linux.com/files/images/standard-unix-filesystem-hierarchypng
|
||||
[4]:https://www.linux.com/sites/lcom/files/styles/rendered_file/public/standard-unix-filesystem-hierarchy.png?itok=CVqmyk6P "filesystem"
|
||||
[5]:https://www.linux.com/licenses/category/used-permission
|
||||
[6]:https://training.linuxfoundation.org/linux-courses/system-administration-training/introduction-to-linux
|
||||
@ -0,0 +1,201 @@
|
||||
# 装载/卸载 Linux 内核模块
|
||||
|
||||
|
||||
|
||||
本文来自 Manning 出版的 [Linux in Action][1] 的第 15 章。
|
||||
|
||||
Linux 使用内核模块管理硬件外设。 我们来看看它是如何工作的。
|
||||
|
||||
运行中的 Linux 内核是您不希望破坏的东西之一。毕竟，内核是驱动计算机所做的一切的软件。考虑到在一个运行的系统上必须同时管理诸多细节，最好能让内核尽可能的减少分心，专心的完成它的工作。但是，如果在不重新启动整个系统的情况下，对计算环境进行任何微小的更改都是不可能的，那么插入一个新的网络摄像头或打印机可能会对您的工作流程造成严重的破坏。每次添加设备时都必须重新启动，以使系统识别它，这效率很低。
|
||||
|
||||
为了在稳定性和可用性之间建立一个有效的平衡，Linux 将内核隔离，但是允许您通过可加载内核模块 (LKMs) 实时添加特定的功能。如下图所示，您可以将模块视为软件的一部分，它告诉内核在哪里找到一个设备以及如何使用它。反过来，内核使设备对用户和进程可用，并监视其操作。
|
||||
|
||||
![Kernel modules][3]
|
||||
|
||||
内核模块充当设备和 Linux 内核之间的转换器。
|
||||
|
||||
没有什么能够阻止你编写你自己的模块来完全按照你喜欢的方式来支持一个设备，但是为什么呢？ Linux 模块库已经非常强大，通常不需要自己去实现一个模块。 而绝大多数时候，Linux 会自动加载新设备的模块，而您甚至不知道它。
|
||||
|
||||
不过，有时候，出于某种原因，它本身并不会运行。 （你不想让那个招聘经理不耐烦地等待你的笑脸加入视频会议面试时间太长。）为了帮助你解决问题，你需要更多地了解内核模块，特别是 ，如何找到运行你的外设的实际模块，然后如何手动激活它。
|
||||
|
||||
### 查找内核模块
|
||||
|
||||
按照公认的约定，模块是位于 `/lib/modules/` 目录下的具有 .ko（内核对象）扩展名的文件。 然而，在你一直导航到这些文件之前，你可能不得不做出选择。 因为在引导时你需要从加载发行版列表中选择一个选项，所以支持您选择的特定软件（包括内核模块）必须存在某处。 那么，`/lib/modules/` 就是其中之一。 你会发现目录里充满了每个可用的 Linux 内核版本的模块; 例如：
|
||||
|
||||
```
|
||||
$ ls /lib/modules
|
||||
|
||||
4.4.0-101-generic
|
||||
|
||||
4.4.0-103-generic
|
||||
|
||||
4.4.0-104-generic
|
||||
|
||||
```
|
||||
|
||||
在我的电脑上，运行的内核是版本号最高的版本（4.4.0-104-generic），但不能保证这对你来说是一样的（内核经常更新）。 如果您将要在一个运行的系统上对你想要使用的模块做一些工作的话，则需要确保您拥有正确的目录树。
|
||||
|
||||
`uname -r`（ `-r` 指定了系统信息中的内核版本号）：
|
||||
|
||||
```
|
||||
$ uname -r
|
||||
|
||||
4.4.0-104-generic
|
||||
|
||||
```
|
||||
|
||||
好消息：有一个可靠的窍门。 不通过名称来识别目录，并希望能够找到正确的目录，而是使用始终指向使用的内核名称的系统变量。 您可以使用（从系统信息中指定通常显示的内核版本号）来调用该变量：
|
||||
|
||||
通过这些信息，您可以使用称为命令替换的过程将 `uname` 并入您的文件系统引用中。 例如，要导航到正确的目录，您需要将其添加到 `/lib/modules` 。 要告诉 Linux “uname” 不是文件系统的位置，请将 `uname` 部分用反引号括起来，如下所示：
|
||||
|
||||
```
|
||||
$ ls /lib/modules/`uname -r`
|
||||
|
||||
build modules.alias modules.dep modules.softdep
|
||||
|
||||
initrd modules.alias.bin modules.dep.bin modules.symbols
|
||||
|
||||
kernel modules.builtin modules.devname modules.symbols.bin
|
||||
|
||||
misc modules.builtin.bin modules.order vdso
|
||||
|
||||
```
|
||||
|
||||
你可以在 `kernel/` 目录下的子目录中找到大部分模块。 花几分钟时间浏览这些目录，了解事物的排列方式和可用内容。 这些文件名通常会让你知道你在看什么。
|
||||
|
||||
```
|
||||
$ ls /lib/modules/`uname -r`/kernel
|
||||
|
||||
arch crypto drivers fs kernel lib mm
|
||||
|
||||
net sound ubuntu virt zfs
|
||||
|
||||
```
|
||||
|
||||
这是查找内核模块的一种方法; 实际上，这是一种快速的方式。 但这不是唯一的方法。 如果你想获得完整的集合，你可以使用 `lsmod` 列出所有当前加载的模块以及一些基本信息。 这个截断输出的第一列（在这里列出的太多了）是模块名称，后面是文件大小和数量，然后是每个模块的名称：
|
||||
|
||||
```
|
||||
$ lsmod
|
||||
|
||||
[...]
|
||||
|
||||
vboxdrv 454656 3 vboxnetadp,vboxnetflt,vboxpci
|
||||
|
||||
rt2x00usb 24576 1 rt2800usb
|
||||
|
||||
rt2800lib 94208 1 rt2800usb
|
||||
|
||||
[...]
|
||||
|
||||
```
|
||||
|
||||
到底有多少？好吧，我们再运行一次 `lsmod ` ，但是这一次将输出管道输送到 `wc -l` 看一下一共多少行:
|
||||
|
||||
```
|
||||
$ lsmod | wc -l
|
||||
|
||||
113
|
||||
|
||||
```
|
||||
|
||||
那些是加载的模块。 总共有多少个？ 运行 `modprobe -c` 并计算这些行将给我们这个数字：
|
||||
|
||||
```
|
||||
$ modprobe -c | wc -l
|
||||
|
||||
33350
|
||||
|
||||
```
|
||||
|
||||
有33,350个可用模块！？！ 看起来好像有人多年来一直在努力为我们提供软件来驱动我们的物理设备。
|
||||
|
||||
注意：在某些系统中，您可能会遇到自定义的模块，这些模块在 `/etc/modules` 文件中使用其唯一条目进行引用，也可以作为保存到 `/etc/modules-load.d/` 的配置文件。这些模块很可能是本地开发项目的产物，可能涉及前沿实验。不管怎样，知道你在看什么是好事。
|
||||
|
||||
这就是你如何找到模块。 如果出于某种原因，它不会自行运行，您的下一个工作就是弄清楚如何手动加载非活动模块。
|
||||
|
||||
### 手动加载内核模块
|
||||
|
||||
在加载内核模块之前，逻辑上您必须确认它的存在。在这之前，你需要知道它叫什么。要做到这一点，有时需要同样的魔法和运气以及在线文档作者的辛勤工作的帮助。
|
||||
|
||||
我将通过描述一段时间前遇到的问题来说明这个过程。在一个晴朗的日子里，出于某种原因，笔记本电脑上的 WiFi 接口停止工作了。就这样。也许是软件升级把它搞砸了。谁知道呢？我运行了 `lshw -c network` ，得到了这个非常奇怪的信息:
|
||||
|
||||
```
|
||||
network UNCLAIMED
|
||||
|
||||
AR9485 Wireless Network Adapter
|
||||
|
||||
```
|
||||
|
||||
Linux 识别到了接口（Atheros AR9485），但将其列为未声明。 那么，正如他们所说的那样，“当情况变得严峻时，就会在互联网上进行艰难的搜索。” 我搜索了一下 atheros ar9 linux 模块，在浏览了 5 页甚至是 10 年前的页面后，它们建议自己写模块或者放弃，然后我终于发现（使用 Ubuntu 16.04， 至少）存在一个工作模块。 它的名字是 ath9k 。
|
||||
|
||||
是的! 这场战斗胜券在握！ 向内核添加模块比听起来容易得多。 要仔细检查它是否可用，可以针对模块的目录树运行 `find`，指定 `-type f` 来告诉 Linux 您正在查找文件，然后将字符串 `ath9k` 和星号一起添加以包含所有以你的字符串打头的文件：
|
||||
|
||||
```
|
||||
$ find /lib/modules/$(uname -r) -type f -name ath9k*
|
||||
|
||||
/lib/modules/4.4.0-97-generic/kernel/drivers/net/wireless/ath/ath9k/ath9k_common.ko
|
||||
|
||||
/lib/modules/4.4.0-97-generic/kernel/drivers/net/wireless/ath/ath9k/ath9k.ko
|
||||
|
||||
/lib/modules/4.4.0-97-generic/kernel/drivers/net/wireless/ath/ath9k/ath9k_htc.ko
|
||||
|
||||
/lib/modules/4.4.0-97-generic/kernel/drivers/net/wireless/ath/ath9k/ath9k_hw.ko
|
||||
|
||||
```
|
||||
|
||||
再一步，加载模块：
|
||||
|
||||
```
|
||||
# modprobe ath9k
|
||||
|
||||
```
|
||||
|
||||
就是这样。没有重新启动。没有大惊小怪。
|
||||
|
||||
这里还有一个示例，向您展示如何使用已经崩溃的运行模块。曾经有一段时间，我使用罗技网络摄像头和一个特定的软件会使摄像头在下次系统启动前无法被任何其他程序访问。有时我需要在不同的应用程序中打开相机，但没有时间关机重新启动。(我运行了很多应用程序，在引导之后将它们全部准备好需要一些时间。)
|
||||
|
||||
由于这个模块可能是运行的，所以使用 `lsmod` 来搜索视频这个词应该给我一个关于相关模块名称的提示。 实际上，它比提示更好：用 video 这个词描述的唯一模块是 uvcvideo（如下所示）：
|
||||
|
||||
```
|
||||
$ lsmod | grep video
|
||||
|
||||
uvcvideo 90112 0
|
||||
|
||||
videobuf2_vmalloc 16384 1 uvcvideo
|
||||
|
||||
videobuf2_v4l2 28672 1 uvcvideo
|
||||
|
||||
videobuf2_core 36864 2 uvcvideo,videobuf2_v4l2
|
||||
|
||||
videodev 176128 4 uvcvideo,v4l2_common,videobuf2_core,videobuf2_v4l2
|
||||
|
||||
media 24576 2 uvcvideo,videodev
|
||||
|
||||
```
|
||||
|
||||
有可能是我自己的操作导致了崩溃，我想我可以挖掘更深一点，看看我能否以正确的方式解决问题。 但你知道它是如何的; 有时你不关心理论，只想让设备工作。 所以我用 `rmmod` 杀死了 `uvcvideo` 模块，然后用 `modprobe` 重新启动它，一切都好：
|
||||
|
||||
```
|
||||
# rmmod uvcvideo
|
||||
|
||||
# modprobe uvcvideo
|
||||
|
||||
```
|
||||
|
||||
再一次：不重新启动。没有其他的后续影响。
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://opensource.com/article/18/5/how-load-or-unload-linux-kernel-module
|
||||
|
||||
作者：[David Clinto][a]
|
||||
选题：[lujun9972](https://github.com/lujun9972)
|
||||
译者：[amwps290](https://github.com/amwps290)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]:https://opensource.com/users/dbclinton
|
||||
[1]:https://www.manning.com/books/linux-in-action?a_aid=bootstrap-it&a_bid=4ca15fc9&chan=opensource
|
||||
[2]:/file/397906
|
||||
[3]:https://opensource.com/sites/default/files/uploads/kernels.png "Kernel modules"
|
||||
@ -1,21 +1,20 @@
|
||||
translating---geekpi
|
||||
|
||||
How To Test A Package Without Installing It In Linux
|
||||
如何在 Linux 中不安装软测试一个软件包
|
||||
======
|
||||
|
||||
For some reason, you might want to test a package before installing it in your Linux system. If so, you’re lucky! Today, I will show you how to do it in Linux using **Nix** package manager. One of the notable feature of Nix package manager is it allows the users to test the packages without having to install them first. This can be helpful when you want to use a particular application temporarily.
|
||||
出于某种原因，你可能需要在将软件包安装到你的 Linux 系统之前对其进行测试。如果是这样，你很幸运！今天，我将向你展示如何在 Linux 中使用 **Nix** 包管理器来实现。Nix 包管理器的一个显著特性是它允许用户测试软件包而无需先安装它们。当你想要临时使用特定的程序时，这会很有帮助。
|
||||
|
||||
### Test A Package Without Installing It In Linux
|
||||
|
||||
Make sure you have installed Nix package manager first. If you haven’t installed it yet, refer the following guide.
|
||||
### 测试一个软件包而不在 Linux 中安装它
|
||||
|
||||
For instance, let us say you want to test your C++ code. You don’t have to install GCC. Just run the following command:
|
||||
确保你先安装了 Nix 包管理器。如果尚未安装，请参阅以下指南。
|
||||
|
||||
例如，假设你想测试你的 C++ 代码。你不必安装 GCC。只需运行以下命令：
|
||||
```
|
||||
$ nix-shell -p gcc
|
||||
|
||||
```
|
||||
|
||||
This command builds or downloads gcc package and its dependencies, then drops you into a Bash shell where the **gcc** command is present, all without affecting your normal environment.
|
||||
该命令会构建或下载 gcc 软件包及其依赖项，然后将其放入一个存在 **gcc** 命令的 Bash shell 中，所有这些都不会影响正常环境。
|
||||
```
|
||||
LANGUAGE = (unset),
|
||||
LC_ALL = (unset),
|
||||
@ -55,7 +54,7 @@ Dload Upload Total Spent Left Speed
|
||||
|
||||
```
|
||||
|
||||
Check the GCC version:
|
||||
检查GCC版本：
|
||||
```
|
||||
[nix-shell:~]$ gcc -v
|
||||
Using built-in specs.
|
||||
@ -68,46 +67,46 @@ gcc version 5.4.0 (GCC)
|
||||
|
||||
```
|
||||
|
||||
Now, go ahead and test the code. Once you are done, type **exit** to return back to your console.
|
||||
现在，继续并测试代码。完成后，输入 **exit** 返回到控制台。
|
||||
```
|
||||
[nix-shell:~]$ exit
|
||||
exit
|
||||
|
||||
```
|
||||
|
||||
Once you are exit from the nix-shell, you can’t use GCC.
|
||||
一旦你从 nix-shell 中退出，你就不能使用 GCC。
|
||||
|
||||
Here is another example.
|
||||
这是另一个例子。
|
||||
```
|
||||
$ nix-shell -p hello
|
||||
|
||||
```
|
||||
|
||||
This builds or downloads GNU Hello and its dependencies, then drops you into a Bash shell where the **hello** command is present, all without affecting your normal environment:
|
||||
这会构建或下载 GNU Hello 和它的依赖关系，然后将其放入 **hello** 命令所在的 Bash shell 中，所有这些都不会影响你的正常环境：
|
||||
```
|
||||
[nix-shell:~]$ hello
|
||||
Hello, world!
|
||||
|
||||
```
|
||||
|
||||
Type exit to return back to the console.
|
||||
输入 exit 返回到控制台。
|
||||
```
|
||||
[nix-shell:~]$ exit
|
||||
|
||||
```
|
||||
|
||||
Now test if hello program is available or not.
|
||||
现在测试你的 hello 程序是否可用。
|
||||
```
|
||||
$ hello
|
||||
hello: command not found
|
||||
|
||||
```
|
||||
|
||||
For more details about Nix package manager, refer the following guide.
|
||||
有关 Nix 包管理器的更多详细信息，请参阅以下指南。
|
||||
|
||||
Hope this helps! More good stuffs to come. Stay tuned!!
|
||||
希望本篇对你有帮助！还会有更好的东西。敬请关注！！
|
||||
|
||||
Cheers!
|
||||
干杯!
|
||||
|
||||
|
||||
|
||||
@ -117,7 +116,7 @@ via: https://www.ostechnix.com/how-to-test-a-package-without-installing-it-in-li
|
||||
|
||||
作者：[SK][a]
|
||||
选题：[lujun9972](https://github.com/lujun9972)
|
||||
译者：[译者ID](https://github.com/译者ID)
|
||||
译者：[geekpi](https://github.com/geekpi)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
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Reference in New Issue
Block a user