Recently we encountered a scenario where our service was not working well after the customer's power outage was restored, because our server A relied on the customer service's server B, but the customer's server B started slower than our server A. So I want to find a way to delay the service startup to solve this problem. After searching for a while, we sorted out a solution suitable for us, using the at command of Linux to achieve delayed startup.
Common execution methods of at (assuming that the task needs to be executed 5 minutes from now):
#执行单条命令
echo "/etc/init.d/your_service restart" | at now +5 minutes
#执行一个脚本
at now +5 minutes -f /home/test/your_script.shTo achieve delayed start of tasks, one condition is required, which is to put the above statement into the task started when Linux is started. This is how Linux manages user-defined boot tasks: /etc/rc.local. The system will execute the contents here after other startup tasks are completed.
Although you can manually edit the /etc/rc.local file with vim directly, the advantage of writing it as a statement is that it facilitates subsequent batch deployment. The time that needs to be delayed can also be implemented by using variable parameters. This is more flexible.