systemd 之下启用 rc.local

不点

从英文网站搜到的，也懒得翻译了。相关知识点整理如下：

1、 rc.local 文件的位置：

/etc/rc.local （通常是这个）
/etc/rc.d/rc.local （在 Fedora、CentOS 之下可能是这个）

应确保 rc.local 是可执行文件。

2、检查 rc-local 服务是否已启用：

sudo systemctl is-enabled rc-local.service

3、检查 rc-local 服务的状态：

sudo systemctl status rc-local.service

4、启用 rc-local 服务：

sudo systemctl enable rc-local.service

5、启用 rc-local 服务之后，只要重启操作系统，就可以自动运行 rc.local 文件了。如果现在不想重启操作系统，那也可以执行如下命令来运行 rc.local 文件：

sudo systemctl start rc-local.service

6、systemd 自带了一个工具（可执行文件），但它没有在 PATH 的路径搜索中：

/lib/systemd/system-generators/systemd-rc-local-generator

猜测这可能只是让系统开发者内部使用的，而不是让终端用户使用的。它有一个 man page：

https://manpages.debian.org/bullseye/systemd/systemd-rc-local-generator.8.en.html

---

【补充】来自：https://blog.wijman.net/enable-rc-local-in-debian-bullseye/

Enable rc.local in Debian Bullseye

By Stephan Wijman   2021-12-03

With Debian 11 (Bullseye) there is no default rc.local file anymore. But this doesn't mean it has been completely removed.

The rc-local service is available but it will need a default config file.

Create a file /etc/rc.local with the following content:

1. #!/bin/sh -e
   
2. #
   
3. # rc.local
   
4. #
   
5. # This script is executed at the end of each multiuser runlevel.
   
6. # Make sure that the script will "exit 0" on success or any other
   
7. # value on error.
   
8. #
   
9. # In order to enable or disable this script just change the execution
   
10. # bits.
    
11. #
    
12. # By default this script does nothing.
    
13. 
    
14. exit 0

复制代码

We now have to make the file executable with the following command:

chmod  +x  /etc/rc.local

Then we need to reload the systemd manager configuration:

systemctl  daemon-reload

Then we start the rc-local daemon:

systemctl  start  rc-local

And then we check the status of rc-local to confirm it ran OK:

systemctl  status  rc-local

You should then get an output like below stating that it is active and exited normally:

1. ● rc-local.service - /etc/rc.local Compatibility
   
2.      Loaded: loaded (/lib/systemd/system/rc-local.service; enabled-runtime; vendor preset: enabled)
   
3.     Drop-In: /usr/lib/systemd/system/rc-local.service.d
   
4.              └─debian.conf     Active: active (exited)
   
5.        Docs: man:systemd-rc-local-generator(8)
   
6.     Process: 58756 ExecStart=/etc/rc.local start (code=exited, status=0/SUCCESS)

复制代码

my9823

各大serivce文件在/etc/systemd/system/目录和/usr/lib/systemd/system目录

my9823

前者有优先于后者。这些个文件大部分都是文本文件。用文本编辑器打开看看，里边有这个service内容，这些依赖那些模，在那些之后或者之前运行，运行命令，与那些命令冲突。initsysv是串行运行，systemd是并行运行的，。可以这样理解，systemd默认以default.target为目标，这个文件也是文本文件，看看它一来那些target,必须在那些target之后运行，找到这些一直往上逆向推回去，就知道启动了哪些脚本命令。

my9823

9527sss

my9823 发表于 2022-7-23 20:12

谢谢分享

9527sss

谢谢分享

su45

谢谢分享

不点

转贴一篇中文的文章            https://blogs.vicsdf.com/article/44516

Debian 11 Bullseye 解决 rc.local 开机启动问题

2022-01-20  by  烧饼          关注作者

本文同样适用于 Debian 10 Buster 和 Debian 9 Strech。

由于某些软件并没有增加开启启动的服务，很多时候需要手工添加，一般我们都是推荐使用 systemd 写个系统服务，但是对于一些简单的脚本或者懒人来说，添加命令到 /etc/rc.local 文件更方便，但是自从 Debian 9 开始，Debian 默认不带 /etc/rc.local 文件，而 rc.local 服务却还是自带的：

1. root@Debian ~ # cat /lib/systemd/system/rc-local.service
   
2. #  SPDX-License-Identifier: LGPL-2.1-or-later##  This file is part of systemd.
   
3. #
   
4. #  systemd is free software; you can redistribute it and/or modify it
   
5. #  under the terms of the GNU Lesser General Public License as published by
   
6. #  the Free Software Foundation; either version 2.1 of the License, or
   
7. #  (at your option) any later version.
   
8. 
   
9. # This unit gets pulled automatically into multi-user.target by
   
10. # systemd-rc-local-generator if /etc/rc.local is executable.
    
11. [Unit]
    
12. Description=/etc/rc.local Compatibility
    
13. Documentation=man:systemd-rc-local-generator(8)
    
14. ConditionFileIsExecutable=/etc/rc.local
    
15. After=network.target
    
16. 
    
17. [Service]
    
18. Type=forking
    
19. ExecStart=/etc/rc.local start
    
20. TimeoutSec=0
    
21. RemainAfterExit=yes
    
22. GuessMainPID=no

复制代码

并且默认情况下这个服务还是关闭的状态：

1. root@debian ~ # systemctl status rc-local
   
2. ● rc-local.service - /etc/rc.local Compatibility
   
3.      Loaded: loaded (/lib/systemd/system/rc-local.service; static)
   
4.     Drop-In: /usr/lib/systemd/system/rc-local.service.d
   
5.              └─debian.conf
   
6.      Active: inactive (dead)
   
7.        Docs: man:systemd-rc-local-generator(8)

复制代码

为了解决这个问题，我们需要手工添加一个 /etc/rc.local 文件：

1. cat <<EOF >/etc/rc.local
   
2. #!/bin/sh -e
   
3. #
   
4. # rc.local
   
5. #
   
6. # This script is executed at the end of each multiuser runlevel.
   
7. # Make sure that the script will "exit 0" on success or any other# value on error.
   
8. #
   
9. # In order to enable or disable this script just change the execution
   
10. # bits.
    
11. #
    
12. # By default this script does nothing.
    
13. 
    
14. exit 0
    
15. EOF

复制代码

然后赋予权限：

1. chmod  +x  /etc/rc.local

复制代码

接着启动 rc-local 服务：

1. systemctl  start  rc-local
   
2. systemctl  enable  rc-local

复制代码

此时可能会弹出警告：

1. The unit files have no installation config (WantedBy=, RequiredBy=, Also=,
   
2. Alias= settings in the [Install] section, and DefaultInstance= for template
   
3. units). This means they are not meant to be enabled using systemctl.
   
4. 
   
5. Possible reasons for having this kind of units are:
   
6. • A unit may be statically enabled by being symlinked from another unit's
   
7.   .wants/ or .requires/ directory.
   
8. • A unit's purpose may be to act as a helper for some other unit which has
   
9.   a requirement dependency on it.
   
10. • A unit may be started when needed via activation (socket, path, timer,
    
11.   D-Bus, udev, scripted systemctl call, ...).
    
12. • In case of template units, the unit is meant to be enabled with some
    
13.   instance name specified.

复制代码

无视警告，因为这个服务没有任何依赖的系统服务，只是开机启动 /etc/rc.local 脚本而已。再次查看状态：

1. root@debian ~ # systemctl status rc-local.service
   
2. ● rc-local.service - /etc/rc.local Compatibility
   
3.      Loaded: loaded (/lib/systemd/system/rc-local.service; enabled-runtime; vendor preset: enabled)
   
4.     Drop-In: /usr/lib/systemd/system/rc-local.service.d
   
5.              └─debian.conf
   
6.      Active: active (exited) since Thu 2022-01-27 18:52:43 UTC; 10s ago
   
7.        Docs: man:systemd-rc-local-generator(8)
   
8.     Process: 541 ExecStart=/etc/rc.local start (code=exited, status=0/SUCCESS)
   
9.         CPU: 3ms
   
10. 
    
11. Jan 27 18:52:43 debian systemd[1]: Starting /etc/rc.local Compatibility...
    
12. Jan 27 18:52:43 debian systemd[1]: Started /etc/rc.local Compatibility.

复制代码

然后你就可以把需要开机启动的命令添加到 /etc/rc.local 文件，丢在 exit 0 前面即可，重启以后试试是否生效了。

作者：烧饼
文章来源： https://u.sb/debian-rc-local/

lianmeng

感谢分享