Article Directory
- 1. Add a self-starting command to the /etc/rc.local file
- 2. Add a self-starting script in the /etc/init.d directory + update-rc.d to add automatic execution actions
- 3. Add a self-starting script in the /etc/init.d directory + add an automatic execution action (busybox) in /etc/inittab
- 4. Create a Linux service and set it to start automatically
- 4. References
1. Add a self-starting command to the /etc/rc.local file
Note: If there is content to add directly, if it does not exist, check whether the following method is used.
example
cat /usr/lib/systemd/system/rc-local.service
#也可能在下面这个路径下
cat /etc/systemd/system/rc-local.service
2. Add a self-starting script in the /etc/init.d directory + update-rc.d to add automatic execution actions
1. Copy or soft link the script to the /etc/init.d/ directory
2. The content of the script is as follows. The content in bold is a template comment and cannot be changed.
cat /etc/init.d/mayue.sh
The content of the script is as follows
#!/bin/sh
echo "mayue.sh 8888" >> /app/mayue.txt
case "$1" in
start)
echo "mayue.sh start" >> /app/mayue.txt
;;
stop)
echo "mayue.sh stop" >> /app/mayue.txt
;;
*)
echo "Usage: /etc/init.d/mayue.sh {start|stop}"
exit 1
;;
esac
exit 0
3. Grant permission to the script file
sudo chmod 755 /etc/init.d/mayue.sh
4. Join the startup
#在ubuntu环境认可的命令、成功后自动添加到对应的rc.d文件夹中
sudo update-rc.d /etc/init.d/mayue.sh defaults 90 #若报错用下面命令
#或
cd /etc/init.d;update-rc.d mayue.sh defaults 90
#在centos环境认可的命令
sudo chkconfig --add mayue.sh && chkconfig mayue.sh on
5. Restart the verification and check the output:
root@imx6qdlsabresd:~# cat /app/mayue.txt
mayue.sh 8888
mayue.sh stop
mayue.sh 8888
mayue.sh start
Since the reboot command is called to stop and then start, the printed content is as above.
3. Add a self-starting script in the /etc/init.d directory + add an automatic execution action (busybox) in /etc/inittab
To add a self-starting program in busybox init, you can follow the steps below:
-
In the BusyBox system, the programs that need to be started automatically can be placed
/etc/init.din the directory. For example, you can put the programs you need to start automatically/etc/init.d/myservicein the directory. -
Create a shell script file in
/etc/init.dthe directory, and the file name is the name of the program you need to start automatically. For example, if your self-starter is namedmyservice, you can/etc/init.dcreate amyserviceshell script file named in the directory. -
In the shell script file you create, write the commands to start the self-starter. For example, if your autostarter is a Python script, you can start it with:
#!/bin/sh python /path/to/myservice.py &In this example,
/path/to/myservice.pyis the path to the Python script you need to start. Use&the symbol to run the script in the background. -
Make the shell script file you created executable. For example, if your self-starting program is called
myservice, you can use the following command to set it as an executable file:chmod +x /etc/init.d/myservice -
Add a reference to the autostart program you created in BusyBox's startup script. For example,
/etc/inittabadd the following lines to the file:::sysinit:/etc/init.d/myserviceThis will automatically run your self-starter program at system startup.
-
Save and restart the BusyBox system, your self-starter should run automatically. You can use
ps auxthe command to check if the program is already running.
3.2 Introduction to /etc/inittab
-
<id>: A unique identifier for a task or service, usually consisting of letters, numbers, and underscores. The value of this field must be unique. -
<runlevels>: Specifies the runlevels under which to start the task or service. Runlevels refer to how the system operates in different states. There are usually 0-6 run levels, where 0 means shutdown, 1 means single-user mode, 2-5 means multi-user mode, and 6 means restart. If you wish to run a task or service in multiple runlevels, you can specify the ranges using comma separators or dashes. -
<action>: Specifies the action to take when the task or service terminates. Commonly used operations are: respawn (restart task or service), wait (wait for task or service to terminate), once (run only once) and off (disable task or service). -
<process>: The process or command to run. This field is usually an absolute path specifying the executable or script to start.
Here's an example line:
my_script:2345:respawn:/path/to/my_script.sh
The value range of action is as follows :
- respawn: If the process exits, restart it.
- once: Start the process only once when init starts, and will not restart after the process exits.
- wait: wait for the process to exit, and then perform the next operation.
- boot: Executes the process at startup, but does not wait for it to exit.
- bootwait: Executes a process at boot time and waits for it to exit.
- sysinit: similar to boot, but executed before starting other services.
- shutdown: Execute the process when the system shuts down.
These actions can be combined as needed to meet different needs.
4. Create a Linux service and set it to start automatically
Take nginx as an example, start it by making a linux service, and set it to start at boot
1) Precondition: nginx has been installed, the default installation path is: /usr/local/nginx
2) Create the nginx.service file under the /etc/systemd/system/ path and write the following content
[Unit]
Description=nginx - high performance web server
After=nginx.service
[Service]
Type=forking
ExecStart=/usr/local/nginx/sbin/nginx
ExecReload=/usr/local/nginx/sbin/nginx -s reload
ExecStop=/usr/local/nginx/sbin/nginx -s stop
Execenable=/usr/local/nginx/sbin/nginx
[Install]
WantedBy=multi-user.target
3) Set the boot to start automatically
# 设置开机启动
systemctl enable nginx
# 取消开机自启动
#systemctl disable nginx
# 查看服务当前状态
systemctl status nginx
# 启动nginx服务
systemctl start nginx
# 停止nginx服务
systemctl stop nginx
# 重启nginx服务
systemctl restart nginx