9. Periodic Processes
Scripting and automation are the keys to consistency and reliability. For example, an adduser program can add new users faster than you can, with a smaller chance of making mistakes. Almost any task can be encoded in a Perl or Python script.
It’s often useful to have a script or command executed without any human intervention. For example, you might want to have a script verify (say, every half-hour) that your network routers and switches are working correctly, and have the script send you email when problems are discovered.1
9.1 CRON: Schedule Commands
The cron daemon is the standard tool for running commands on a predetermined ...