document/TranslateProject
2
0
Fork 0
mirror of https://github.com/LCTT/TranslateProject.git synced 2024-12-26 21:30:55 +08:00
Code Issues Packages Projects Releases Wiki Activity

翻译完成

Browse Source
This commit is contained in:
MjSeven 2022-10-16 20:04:03 +08:00
parent 791989d3a7
commit 5b20980eda
2 changed files with 327 additions and 323 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

323
sources/tech/20220919 How To Find Default Gateway IP Address In Linux And Unix From Commandline.md
View File

@ -1,323 +0,0 @@
[#]: subject: "How To Find Default Gateway IP Address In Linux And Unix From Commandline"
[#]: via: "https://ostechnix.com/find-default-gateway-linux/"
[#]: author: "sk https://ostechnix.com/author/sk/"
[#]: collector: "lkxed"
[#]: translator: "MjSeven"
[#]: reviewer: " "
[#]: publisher: " "
[#]: url: " "
How To Find Default Gateway IP Address In Linux And Unix From Commandline
======
5 Ways To Find Gateway Or Router IP Address In Linux
A **gateway** is a node or a router that allows two or more hosts with different IP addresses to communicate with each other when connected to the same router. Without gateway, devices connected on the same router won’t be able to communicate with each other. To put this another way, the gateway acts as an access point to pass network data from a local network to a remote network. In this guide, we will see all the possible ways to **find default gateway in Linux** and **Unix** from commandline.
#### Contents
1. Find Default Gateway In Linux 2. 1. Find Default Gateway Using ip Command 3. 2. Display Default Gateway IP Address Using route Command 4. 3. View Gateway IP Address Using netstat Command 5. 4. Print Default Gateway IP Address Or Router IP Address Using routel Command 6. 5. Find Gateway From Ethernet Configuration Files
7. Conclusion
### Find Default Gateway In Linux
There are various commandline tools are available to view the gateway IP address in Linux. The most commonly used tools are: **ip**, **ss**, and **netcat**. We will see how check the default gateway using each tool with examples.
#### 1. Find Default Gateway Using ip Command
The **ip** command is used to show and manipulate routing, network devices, interfaces and tunnels in Linux.
To find the default gateway or Router IP address, simply run:
```
$ ip route
```
Or,
```
$ ip r
```
Or,
```
$ ip route show
```
**Sample output:**
```
default via 192.168.1.101 dev eth0 proto static metric 100
172.17.0.0/16 dev docker0 proto kernel scope link src 172.17.0.1 linkdown
192.168.1.0/24 dev eth0 proto kernel scope link src 192.168.1.20 metric 100
```
Did you see the line **"default via 192.168.1.101"** in the above output? This is the default gateway. So my default gateway is **192.168.1.101**.
You can use **-4** with `ip route` command to **display the IPv4 gateway** only:
```
$ ip -4 route
```
And, use `-6` to **display the IPv6 gateway** only:
```
$ ip -6 route
```
As you noticed in the output, the IP address and the subnet details are also shown. If you want to display ONLY the default gateway and exclude all other details from the output, you can use `awk` command with `ip route` like below.
To find the default gateway IP address using `ip route` and `grep`, run:
To print Gateway IP address with `ip route` and `awk` commands, run:
```
$ ip route | awk '/^default/{print $3}'
```
Or,
```
$ ip route show default | awk '{print $3}'
```
This will list only the gateway.
**Sample output:**
```
192.168.1.101
```
![Find Default Gateway Using ip Command][1]
You can also use **[grep][2]** command with `ip route` to filter the default gateway.
```
$ ip route | grep default
default via 192.168.1.101 dev eth0 proto static metric 100
```
The `ip route` is the recommended command to find the default gateway IP address in latest Linux distributions. However, some of you may still be using the legacy tools like **route** and `netstat`. Old habits die hard, right? The following sections explains how to determine the gateway in Linux using `route` and `netstat` commands.
#### 2. Display Default Gateway IP Address Using route Command
The **route** command is used to show and manipulate routing table in older Linux distributions, for example RHEL 6, CentOS 6.
If you're using those older Linux distributions, you can use the `route` command to display the default gateway.
Please note that the `route` tool is deprecated and replaced with `ip route` command in the latest Linux distributions. If you still want to use `route` for any reason, you need to install it.
First, we need to check which package provides `route` command. To do so, run the following command on your RHEL-based system:
```
$ dnf provides route
```
**Sample output:**
```
net-tools-2.0-0.52.20160912git.el8.x86_64 : Basic networking tools
Repo : @System
Matched from:
Filename : /usr/sbin/route
net-tools-2.0-0.52.20160912git.el8.x86_64 : Basic networking tools
Repo : baseos
Matched from:
Filename : /usr/sbin/route
```
As you can see in the above output, the net-tools package provides the `route` command. So, let us install it using command:
```
$ sudo dnf install net-tools
```
Now, run `route` command with `-n` flag to display the gateway IP address or router IP address in your Linux system:
```
$ route -n
```
**Sample output:**
```
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
0.0.0.0 192.168.1.101 0.0.0.0 UG 100 0 0 eth0
172.17.0.0 0.0.0.0 255.255.0.0 U 0 0 0 docker0
192.168.1.0 0.0.0.0 255.255.255.0 U 100 0 0 eth0
```
![Display Default Gateway IP Address Using route Command][3]
As you see in the above output, the gateway IP address is 192.168.1.101. You will also see the two letters **"UG"** under Flags section. The letter **"U"** indicates the interface is **UP** and **G** stands for Gateway.
#### 3. View Gateway IP Address Using netstat Command
**Netstat** prints information about the Linux networking subsystem. Using netstat tool, we can print network connections, routing tables, interface statistics, masquerade connections, and multicast memberships in Linux and Unix systems.
Netstat is part of net-tools package, so make sure you've installed it in your Linux system. The following commands install net-tools package in RHEL-based systems:
```
$ sudo dnf install net-tools
```
To print the default gateway IP address using `netstat` command, run:
```
$ netstat -rn
```
**Sample output:**
```
Kernel IP routing table
Destination Gateway Genmask Flags MSS Window irtt Iface
0.0.0.0 192.168.1.101 0.0.0.0 UG 0 0 0 eth0
172.17.0.0 0.0.0.0 255.255.0.0 U 0 0 0 docker0
192.168.1.0 0.0.0.0 255.255.255.0 U 0 0 0 eth0
```
![View Gateway IP Address Using netstat Command][4]
The `netstat` command's output is same as `route` command's output. As per the above output, the gateway IP address is 192.168.1.101 and the UG stands the NIC associated to gateway is UP and G indicates Gateway,
Please note that `netstat` is also deprecated and it is recommended to use **"ss"** command instead of netstat.
#### 4. Print Default Gateway IP Address Or Router IP Address Using routel Command
The **routel** is a script to list routes with pretty output format. The routel script will list routes in a format that some might consider easier to interpret then the `ip route` list equivalent.
The routel script is also the part of net-tools package.
To print the default gateway or router IP address, run routel script without any flags like below:
```
$ routel
```
**Sample output:**
```
target gateway source proto scope dev tbl
default 192.168.1.101 static eth0
172.17.0.0/ 16 172.17.0.1 kernel linkdocker0
192.168.1.0/ 24 192.168.1.20 kernel link eth0
127.0.0.0/ 8 local 127.0.0.1 kernel host lo local
127.0.0.1 local 127.0.0.1 kernel host lo local
127.255.255.255 broadcast 127.0.0.1 kernel link lo local
172.17.0.1 local 172.17.0.1 kernel hostdocker0 local
172.17.255.255 broadcast 172.17.0.1 kernel linkdocker0 local
192.168.1.20 local 192.168.1.20 kernel host eth0 local
192.168.1.255 broadcast 192.168.1.20 kernel link eth0 local
::1 kernel lo
::/ 96 unreachable lo
::ffff:0.0.0.0/ 96 unreachable lo
2002:a00::/ 24 unreachable lo
2002:7f00::/ 24 unreachable lo
2002:a9fe::/ 32 unreachable lo
2002:ac10::/ 28 unreachable lo
2002:c0a8::/ 32 unreachable lo
2002:e000::/ 19 unreachable lo
3ffe:ffff::/ 32 unreachable lo
fe80::/ 64 kernel eth0
::1 local kernel lo local
fe80::d085:cff:fec7:c1c3 local kernel eth0 local
```
![Print Default Gateway IP Address Or Router IP Address Using routel Command][5]
To print only the default gateway, run routel with `grep` like below:
```
$ routel | grep default
default 192.168.1.101 static eth0
```
#### 5. Find Gateway From Ethernet Configuration Files
If you have **[configured static IP address in your Linux or Unix][6]** system, you can view the default gateway or router IP address by looking at the network configuration files.
In RPM-based systems like Fedora, RHEL, CentOS, AlmaLinux and Rocky Linux, the network interface card (shortly **NIC**) configuration are stored under **/etc/sysconfig/network-scripts/** directory.
Find the name of the network card:
```
# ip link show
```
**Sample output:**
```
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN mode DEFAULT group default qlen 1000
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
2: eth0@if5: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP mode DEFAULT group default qlen 1000
link/ether d2:85:0c:c7:c1:c3 brd ff:ff:ff:ff:ff:ff link-netnsid 0
```
The network card name is **eth0**. So let us open the network card configuration of this NIC card file:
```
# cat /etc/sysconfig/network-scripts/ifcfg-eth0
```
**Sample output:**
```
DEVICE=eth0
ONBOOT=yes
UUID=eb6b6a7c-37f5-11ed-a59a-a0e70bdf3dfb
BOOTPROTO=none
IPADDR=192.168.1.20
NETMASK=255.255.255.0
GATEWAY=192.168.1.101
DNS1=8.8.8.8
```
As you see above, the gateway IP is `192.168.1.101`.
In Debian, Ubuntu and its derivatives, all network configuration files are stored under **/etc/network/** directory.
```
$ cat /etc/network/interfaces
```
**Sample output:**
```
auto ens18
iface ens18 inet static
address 192.168.1.150
netmask 255.255.255.0
gateway 192.168.1.101
dns-nameservers 8.8.8.8
```
Please note that this method should work only if the IP address is configured manually. For DHCP-enabled network, you need to follow the previous 4 methods.
### Conclusion
In this guide, we listed 5 different ways to find default gateway in Linux and Unix operating systems. We also have included sample commands to display the gateway/router IP address in each method. Hope this helps.
--------------------------------------------------------------------------------
via: https://ostechnix.com/find-default-gateway-linux/
作者：[sk][a]
选题：[lkxed][b]
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://ostechnix.com/author/sk/
[b]: https://github.com/lkxed
[1]: https://ostechnix.com/wp-content/uploads/2022/09/Find-Default-Gateway-Using-ip-Command.png
[2]: https://ostechnix.com/the-grep-command-tutorial-with-examples-for-beginners/
[3]: https://ostechnix.com/wp-content/uploads/2022/09/Display-Default-Gateway-IP-Address-Using-route-Command.png
[4]: https://ostechnix.com/wp-content/uploads/2022/09/View-Gateway-IP-Address-Using-netstat-Command.png
[5]: https://ostechnix.com/wp-content/uploads/2022/09/Print-Default-Gateway-IP-Address-Or-Router-IP-Address-Using-routel-Command.png
[6]: https://ostechnix.com/configure-static-ip-address-linux-unix/

327
translated/tech/20220919 How To Find Default Gateway IP Address In Linux And Unix From Commandline.md Normal file
View File

@ -0,0 +1,327 @@
[#]: subject: "How To Find Default Gateway IP Address In Linux And Unix From Commandline"
[#]: via: "https://ostechnix.com/find-default-gateway-linux/"
[#]: author: "sk https://ostechnix.com/author/sk/"
[#]: collector: "lkxed"
[#]: translator: "MjSeven"
[#]: reviewer: " "
[#]: publisher: " "
[#]: url: " "
在 Linux 和 Unix 中如何从命令行查找默认网关的 IP 地址
======
Linux 下查找网关或路由器 IP 地址的 5 种方法。
**网关**是一个节点或一个路由器，当连接到同一路由器时，它允许两个或多个 IP 地址不同的主机相互通信。如果没有网关，它们将无法相互通信。换句话说，网关充当接入点，将网络数据从本地网络传输到远程网络。在本指南中，我们将看到在 Linux 和 Unix 中从命令行找到默认网关的所有可能方法。
#### 内容
1. 在 Linux 中查找默认网关 1.1 使用 ip 命令查找默认网关 1.2 使用 route 命令显示默认网关 IP 地址 1.3 使用 netstat 命令查看网关 IP 地址 1.4 使用 routel 命令打印默认网关或路由器 IP 地址 1.5 从以太网配置文件中查找网关
2. 总结
### 在 Linux 中查找默认网关
Linux 中有各种各样的命令行工具可用于查看网关 IP 地址。最常用的工具是：**ip**、**ss** 和 **netcat**。我们将通过示例了解如何使用每种工具查看默认网关。
#### 1. 使用 ip 命令查找默认网关
**ip** 命令用于显示和操作 Linux 中的路由、网络设备、接口和隧道。
要查找默认网关或路由器 IP 地址，只需运行：
```
$ ip route
```
或者：
```
$ ip r
```
或者：
```
$ ip route show
```
**示例输出：**
```
default via 192.168.1.101 dev eth0 proto static metric 100
172.17.0.0/16 dev docker0 proto kernel scope link src 172.17.0.1 linkdown
192.168.1.0/24 dev eth0 proto kernel scope link src 192.168.1.20 metric 100
```
你从输出中看到了 **"default via 192.168.1.101"** 这一行吗？它就是默认网关。我的默认网关是 **192.168.1.101**。
你可以使用 **-4** 参数只**显示 IPv4 网关**：
```
$ ip -4 route
```
或者，使用 **`-6`** 参数只**显示 IPv6 网关**：
```
$ ip -6 route
```
如你所见，IP 地址和子网详细信息也一并显示了。如果你想只显示默认网关，排除所有其他细节，可以使用 `ip route` 搭配 **`awk`** 命令，如下所示。
使用 `ip route` 和 `grep` 查找默认网关 IP 地址，执行命令：
```（to 校正，此条命令原文无，怀疑是作者忘记加了）
$ ip route | grep default
```
使用 `ip route` 和 `awk` 命令打印网关地址，执行命令：
```（to 校正，译注：wsl1 上无输出结果，正常 Linux 发行版无问题）
$ ip route | awk '/^default/{print $3}'
```
或者：
```
$ ip route show default | awk '{print $3}'
```
这将只列出网关 IP：
**示例输出：**
```
192.168.1.101
```
![使用 ip 命令列出默认网关][1]
你也可以使用 **[grep][2]** 命令配合 `ip route` 对默认网关进行过滤。
```
$ ip route | grep default
default via 192.168.1.101 dev eth0 proto static metric 100
```
在最新的 Linux 发行版中，`ip route` 是查找默认网关 ip 地址的推荐命令。然而，你们中的一些人可能仍然在使用传统的工具，如 `route` 和 **`netstat`**。旧习难改，对吧？下面的部分将介绍如何在 Linux 中使用 `route` 和 `netstat` 命令确定网关。
#### 2. 使用 route 命令显示默认网关 IP 地址
**route** 命令用于在较老的 Linux 发行版中显示和操作路由表，如 RHEL 6、CentOS 6 等。
如果你正在使用较老的 Linux 发行版，你可以使用 `route` 命令来显示默认网关。
请注意，在最新的 Linux 发行版中，`route` 工具已被弃用，`ip route` 命令取而代之。如果你因为某些原因仍然想使用 `route`，你需要安装它。
首先，我们需要检查哪个包提供了 `route` 命令。为此，在基于 RHEL 的系统上运行以下命令：
```
$ dnf provides route
```
**示例输出：**
```
net-tools-2.0-0.52.20160912git.el8.x86_64 : Basic networking tools
Repo : @System
Matched from:
Filename : /usr/sbin/route
net-tools-2.0-0.52.20160912git.el8.x86_64 : Basic networking tools
Repo : baseos
Matched from:
Filename : /usr/sbin/route
```
如你所见，net-tools 包提供了 `route` 命令。所以，让我们使用以下命令来安装它：
```
$ sudo dnf install net-tools
```
现在，运行带有 `-n` 参数的 `route` 命令来显示 Linux 系统中的网关或路由器 IP 地址：
```
$ route -n
```
**示例输出：**
```
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
0.0.0.0 192.168.1.101 0.0.0.0 UG 100 0 0 eth0
172.17.0.0 0.0.0.0 255.255.0.0 U 0 0 0 docker0
192.168.1.0 0.0.0.0 255.255.255.0 U 100 0 0 eth0
```
![使用 route 命令显示默认网关 IP 地址][3]
如你所见，网关 IP 地址是 192.168.1.101。你还将在 Flags 下面看到两个字母 **UG**。字母 **U** 代表接口是 **UP**，**G** 表示网关。
#### 3. 使用 netstat 命令查看网关 IP 地址
**Netstat** 会输出 Linux 网络子系统的信息。使用 netstat 工具，我们可以在 Linux 和 Unix 系统中打印网络连接、路由表、接口统计信息、伪装连接和组播成员关系。
Netstat 是 net-tools 包的一部分，所以确保你已经在 Linux 系统中安装了它。使用以下命令在基于 RHEL 的系统中安装它：
```
$ sudo dnf install net-tools
```
使用 netstat 命令打印默认网关 IP 地址：
```
$ netstat -rn
```
**示例输出：**
```
Kernel IP routing table
Destination Gateway Genmask Flags MSS Window irtt Iface
0.0.0.0 192.168.1.101 0.0.0.0 UG 0 0 0 eth0
172.17.0.0 0.0.0.0 255.255.0.0 U 0 0 0 docker0
192.168.1.0 0.0.0.0 255.255.255.0 U 0 0 0 eth0
```
![使用 netstat 命令查看网关 IP 地址][4]
`netstat` 命令与 `route` 命令的输出信息相同。如上输出可知，网关的 IP 地址为 192.168.1.191，UG 表示网关连接的网卡（NIC）是有效的，G 表示网关。
请注意 `netstat` 也已弃用，建议使用 **ss** 命令代替 netstat。
#### 4. 使用 routel 命令打印默认网关或路由器 IP 地址
**routel** 是一个脚本，它以一种漂亮格式的输出路由。routel 脚本的输出让一些人认为比 `ip route` 列表更直观。
routel 脚本也是 net-tools 包的一部分。
打印默认网关或路由器 IP 地址，运行 routel 脚本，不带任何参数，如下所示：
```
$ routel
```
**示例输出：**
```
target gateway source proto scope dev tbl
default 192.168.1.101 static eth0
172.17.0.0/ 16 172.17.0.1 kernel linkdocker0
192.168.1.0/ 24 192.168.1.20 kernel link eth0
127.0.0.0/ 8 local 127.0.0.1 kernel host lo local
127.0.0.1 local 127.0.0.1 kernel host lo local
127.255.255.255 broadcast 127.0.0.1 kernel link lo local
172.17.0.1 local 172.17.0.1 kernel hostdocker0 local
172.17.255.255 broadcast 172.17.0.1 kernel linkdocker0 local
192.168.1.20 local 192.168.1.20 kernel host eth0 local
192.168.1.255 broadcast 192.168.1.20 kernel link eth0 local
::1 kernel lo
::/ 96 unreachable lo
::ffff:0.0.0.0/ 96 unreachable lo
2002:a00::/ 24 unreachable lo
2002:7f00::/ 24 unreachable lo
2002:a9fe::/ 32 unreachable lo
2002:ac10::/ 28 unreachable lo
2002:c0a8::/ 32 unreachable lo
2002:e000::/ 19 unreachable lo
3ffe:ffff::/ 32 unreachable lo
fe80::/ 64 kernel eth0
::1 local kernel lo local
fe80::d085:cff:fec7:c1c3 local kernel eth0 local
```
![使用 routel 命令打印默认网关或路由器 IP 地址][5]
只打印默认网关，和 `grep` 命令配合，如下所示：
```
$ routel | grep default
default 192.168.1.101 static eth0
```
#### 5. 从以太网配置文件中查找网关
如果你在 **[Linux 或 Unix 中配置了静态 IP 地址][6]，你可以通过查看网络配置文件查看默认网关或路由器 IP 地址。
在基于 RPM 的系统上，如 Fedora、RHEL、CentOS、AlmaLinux 和 Rocky Linux 等，网络接口卡（简称 **NIC**）配置存储在 **/etc/sysconfig/network-scripts/** 目录下。
查找网卡的名称：
```
# ip link show
```
**示例输出：**
```
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN mode DEFAULT group default qlen 1000
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
2: eth0@if5: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP mode DEFAULT group default qlen 1000
link/ether d2:85:0c:c7:c1:c3 brd ff:ff:ff:ff:ff:ff link-netnsid 0
```
网卡名为 **eth0**。所以让我们打开这个 NIC 文件的网卡配置：
```
# cat /etc/sysconfig/network-scripts/ifcfg-eth0
```
**示例输出：**
```
DEVICE=eth0
ONBOOT=yes
UUID=eb6b6a7c-37f5-11ed-a59a-a0e70bdf3dfb
BOOTPROTO=none
IPADDR=192.168.1.20
NETMASK=255.255.255.0
GATEWAY=192.168.1.101
DNS1=8.8.8.8
```
如你所见，网关 IP 为 `192.168.1.101`。
在 Debian、Ubuntu 及其衍生版中，所有的网络配置文件都存储在 **/etc/network** 目录下。
```
$ cat /etc/network/interfaces
```
**示例输出：**
```
auto ens18
iface ens18 inet static
address 192.168.1.150
netmask 255.255.255.0
gateway 192.168.1.101
dns-nameservers 8.8.8.8
```
请注意，此方法仅在手动配置 IP 地址时有效。对于启用 DHCP 的网络，需要按照前面的 4 种方法操作。
### 总结
在本指南中，我们列出了在 Linux 和 Unix 系统中找到默认网关的 5 种不同方法，我们还在每种方法中包含了显示网关/路由器 IP 地址的示例命令。希望它对你有所帮助。
--------------------------------------------------------------------------------
via: https://ostechnix.com/find-default-gateway-linux/
作者：[sk][a]
选题：[lkxed][b]
译者：[MjSeven](https://github.com/MjSeven)
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://ostechnix.com/author/sk/
[b]: https://github.com/lkxed
[1]: https://ostechnix.com/wp-content/uploads/2022/09/Find-Default-Gateway-Using-ip-Command.png
[2]: https://ostechnix.com/the-grep-command-tutorial-with-examples-for-beginners/
[3]: https://ostechnix.com/wp-content/uploads/2022/09/Display-Default-Gateway-IP-Address-Using-route-Command.png
[4]: https://ostechnix.com/wp-content/uploads/2022/09/View-Gateway-IP-Address-Using-netstat-Command.png
[5]: https://ostechnix.com/wp-content/uploads/2022/09/Print-Default-Gateway-IP-Address-Or-Router-IP-Address-Using-routel-Command.png
[6]: https://ostechnix.com/configure-static-ip-address-linux-unix/