System Services

System Services

Linux systems rely heavily on five systems services; init, inetd, xinetd, syslog, and cron. These systems, while relatively simple in structure, handle many of the most important elements of the Linux OS. They are, to a large extent, the crucial elements of the power and speed with which a well-configured Linux system operates. Over the next few days, we’ll look at these services and focus on the tools necessary to better tune them to your particular system.

The init process is the mother of all processes. This service is the first to start in any Linux system and serves as the highest-level parent process. It’s always running, waiting for system calls from other processes. Init has a process id of 1. Should a process fail before all its spawned child processes complete their work, init will inherit those children, becoming the parent process until their completion. Take a look at the results of the command ps -af to see which current processes on your Linux system have init as the parent.

Monday, we’ll look at how a simple file, /etc/initab, defines the behavior of init in handling runlevels.