mirror of
https://github.com/LCTT/TranslateProject.git
synced 2025-01-31 23:30:11 +08:00
77 lines
2.9 KiB
Markdown
77 lines
2.9 KiB
Markdown
|
[#]: collector: (lujun9972)
|
|||
|
[#]: translator: ( )
|
|||
|
[#]: reviewer: ( )
|
|||
|
[#]: publisher: ( )
|
|||
|
[#]: url: ( )
|
|||
|
[#]: subject: (Understanding /etc/services file in Linux)
|
|||
|
[#]: via: (https://kerneltalks.com/linux/understanding-etc-services-file-in-linux/)
|
|||
|
[#]: author: (kerneltalks https://kerneltalks.com)
|
|||
|
|
|||
|
Understanding /etc/services file in Linux
|
|||
|
======
|
|||
|
|
|||
|
Article which helps you to understand /etc/services file in Linux. Learn about content, format & importance of this file.
|
|||
|
|
|||
|
![/etc/services file in Linux][1]
|
|||
|
/etc/services file in Linux
|
|||
|
|
|||
|
Internet daemon is important service in Linux world. It takes care of all network services with the help of `/etc/services` file. In this article we will walk you through content, format of this file and what it means to a Linux system.
|
|||
|
|
|||
|
`/etc/services` file contains list of network services and ports mapped to them. `inetd` or `xinetd` looks at these details so that it can call particular program when packet hits respective port and demand for service.
|
|||
|
|
|||
|
As a normal user you can view this file since file is world readable. To edit this file you need to have root privileges.
|
|||
|
|
|||
|
```
|
|||
|
$ ll /etc/services
|
|||
|
-rw-r--r--. 1 root root 670293 Jun 7 2013 /etc/services
|
|||
|
```
|
|||
|
|
|||
|
### `/etc/services` file format
|
|||
|
|
|||
|
```
|
|||
|
service-name port/protocol [aliases..] [#comment]
|
|||
|
```
|
|||
|
|
|||
|
Last two fields are optional hence denoted in `[` `]`
|
|||
|
|
|||
|
where –
|
|||
|
|
|||
|
* service-name is name of the network service. e.g. [telnet][2], [ftp][3] etc.
|
|||
|
* port/protocol is port being used by that network service (numerical value) and protocol (TCP/UDP) used for communication by service.
|
|||
|
* alias is alternate name for service.
|
|||
|
* comment is note or description you can add to service. Starts with `#` mark
|
|||
|
|
|||
|
|
|||
|
|
|||
|
### Sample` /etc/services` file
|
|||
|
|
|||
|
```
|
|||
|
# Each line describes one service, and is of the form:
|
|||
|
#
|
|||
|
# service-name port/protocol [aliases ...] [# comment]
|
|||
|
|
|||
|
tcpmux 1/tcp # TCP port service multiplexer
|
|||
|
rje 5/tcp # Remote Job Entry
|
|||
|
echo 7/udp
|
|||
|
discard 9/udp sink null
|
|||
|
```
|
|||
|
|
|||
|
Here, you can see use of optional last two fields as well. `discard` service has alternate name as `sink` or `null`.
|
|||
|
|
|||
|
--------------------------------------------------------------------------------
|
|||
|
|
|||
|
via: https://kerneltalks.com/linux/understanding-etc-services-file-in-linux/
|
|||
|
|
|||
|
作者:[kerneltalks][a]
|
|||
|
选题:[lujun9972][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://kerneltalks.com
|
|||
|
[b]: https://github.com/lujun9972
|
|||
|
[1]: https://i2.wp.com/kerneltalks.com/wp-content/uploads/2019/01/undestanding-etc-service-file-in-linux.png?ssl=1
|
|||
|
[2]: https://kerneltalks.com/config/configure-telnet-server-linux/
|
|||
|
[3]: https://kerneltalks.com/config/ftp-server-configuration-steps-rhel-6/
|