某些软件并添加开启启动的服务，很多时候需要手动不添加，一般我们都是推荐添加到/etc/rc.local文件，但是Debian 11默认不带/etc/rc.local文件，而rc.local服务却还是自带的
查看默认rc.local服务文件：cat /lib/systemd/system/rc.local.service
# This file is part of systemd.
#
# systemd is free software; you can redistribute it and/or modify it
# under the terms of the GNU Lesser General Public License as published by
# the Free Software Foundation; either version 2.1 of the License, or
# (at your option) any later version.
# This unit gets pulled automatically into multi-user.target by
# systemd-rc-local-generator if /etc/rc.local is executable.
[Unit]
Description=/etc/rc.local Compatibility
ConditionFileIsExecutable=/etc/rc.local
After=network.target
[Service]
Type=forking
ExecStart=/etc/rc.local start
TimeoutSec=0
RemainAfterExit=yes
GuessMainPID=no
并且默认情况下这个服务还是关闭的状态
systemctl status rc-local 查看状态显示如下：
● rc-local.service - /etc/rc.local Compatibility
Loaded: loaded (/lib/systemd/system/rc-local.service; static; vendor preset: enabled)
Drop-In: /lib/systemd/system/rc-local.service.d
└─debian.conf
Active: inactive (dead)
为了解决这个问题，我们需要手动添加一个vi /etc/rc.local文件
sudo touch /etc/rc.local
编辑相应文件vi /etc/rc.local输入以下内容：
#!/bin/bash
#
# rc.local
#
# This script is executed at the end of each multiuser runlevel.
# Make sure that the script will "exit 0" on success or any other
# value on error.
#
# In order to enable or disable this script just change the execution
# bits.
#
# By default this script does nothing.
exit 0
设置权限 chmod +x /etc/rc.local
启动rc-local服务 systemctl start rc-local
再次查看状态 systemctl status rc-local
显示如下：
● rc-local.service - /etc/rc.local Compatibility
Loaded: loaded (/lib/systemd/system/rc-local.service; static; vendor preset: enabled)
Drop-In: /lib/systemd/system/rc-local.service.d
└─debian.conf
Active: active (exited) since Thu 2017-08-03 09:41:18 UTC; 14s ago
Process: 20901 ExecStart=/etc/rc.local start (code=exited, status=0/SUCCESS)
Aug 03 09:41:18 xtom-hk systemd[1]: Starting /etc/rc.local Compatibility...
Aug 03 09:41:18 xtom-hk systemd[1]: Started /etc/rc.local Compatibility.
然后你就可以把需要启动的命令放到/etc/rc.local中了，（exit 0之前）
尝试重启作为命令生效。
编辑rc-local.service
sudo vim /etc/systemd/system/rc-local.service
在文件中写入如下内容：
# SPDX-License-Identifier: LGPL-2.1-or-later
#
# This file is part of systemd.
#
# systemd is free software; you can redistribute it and/or modify it
# under the terms of the GNU Lesser General Public License as published by
# the Free Software Foundation; either version 2.1 of the License, or
# (at your option) any later version.
# This unit gets pulled automatically into multi-user.target by
# systemd-rc-local-generator if /etc/rc.local is executable.
[Unit]
Description=/etc/rc.local Compatibility
Documentation=man:systemd-rc-local-generator(8)
ConditionFileIsExecutable=/etc/rc.local
After=network.target
[Service]
Type=forking
ExecStart=/etc/rc.local start
TimeoutSec=0
RemainAfterExit=yes
GuessMainPID=no
[Install]
WantedBy=multi-user.target
保存。
或利用系统默认文件建立软连接
ln -s /usr/lib/systemd/system/rc-local.service /etc/systemd/system/rc-local.service
编辑rc-local.service
sudo vim /etc/systemd/system/rc-local.service
加入字段[Install]
[Install]
WantedBy=multi-user.target
保存。
2、终端一键写入方式创建rc-local.service文件：
sudo echo "
# SPDX-License-Identifier: LGPL-2.1-or-later
#
# This file is part of systemd.
#
# systemd is free software; you can redistribute it and/or modify it
# under the terms of the GNU Lesser General Public License as published by
# the Free Software Foundation; either version 2.1 of the License, or
# (at your option) any later version.
# This unit gets pulled automatically into multi-user.target by
# systemd-rc-local-generator if /etc/rc.local is executable.
[Unit]
Description=/etc/rc.local Compatibility
Documentation=man:systemd-rc-local-generator(8)
ConditionFileIsExecutable=/etc/rc.local
After=network.target
[Service]
Type=forking
ExecStart=/etc/rc.local start
TimeoutSec=0
RemainAfterExit=yes
GuessMainPID=no
[Install]
WantedBy=multi-user.target
" >> etc/systemd/system/rc-local.service
3.接下来就是创建一个rc.local：
sudo touch /etc/rc.local
编辑 rc.local
sudo vi /etc/rc.local
写入以下内容：
#!/bin/sh -e
#
# rc.local
#
# This script is executed at the end of each multiuser runlevel.
# Make sure that the script will "exit 0" on success or any other
# value on error.
#
# In order to enable or disable this script just change the execution
# bits.
#
# By default this script does nothing.
exit 0
在 exit 0 行前面添加待开机启动的命令：
# 示例：后台启动chfs服务：
nohup /usr/local/app/chfs/chfs --file /usr/local/app/chfs/chfs.ini &
# 示例：挂载Samba共享
mount -t cifs -o username=User,password=Admin-1113,gid=0,uid=0, //192.168.1.52/数据盘 /mnt/SMB
exit 0
给rc.local 添加执行的权限
sudo chmod +x /etc/rc.local
4.接下来是启动服务：
①.刷新systemctl配置
systemctl daemon-reload
②.设置开机启动
systemctl enable rc-local.service
③.启动服务
sudo systemctl start rc-local.service
④.测试服务的状态
sudo systemctl status rc-local.service
