If you really want to see what's happening beneath the hood of your Linux distribution, you need to use log files.

If you’re a systems administrator, you know the importance of log files. Without those crucial bits of saved information, you might not know where to start troubleshooting issues on your servers ...

With tail, you can view a Linux log file as the system writes to it in real time. So while you’re trying to troubleshoot that system, you can follow the syslog, the auth.log, faillog, kern.log ...

Linux system log files are by default set to rotate. Depending on the age or size, a sequence of files moves back a step, the oldest being removed and a new one taking over as the current log file ...