Chapter Summary

The system-config-users utility adds new users and groups to the system and modifies existing users' accounts. You can also use the equivalent command line tools (useradd, usermod, userdel, groupadd, and groupmod) to work with user accounts. Backing up files on the system is a critical and often overlooked part of system administration. Linux includes the tar, cpio, dump, and restore utilities to back up and restore files. You can also use more sophisticated packages such as amanda and various commercial products.

The system scheduling daemon, cron, periodically executes scheduled tasks. You can schedule tasks using crontab, at, and KDE's kcron. System reports present information on the health of the system. Two useful tools that generate these reports are vmstat, which details virtual memory, I/O, and CPU statistics, and top, which reports on how the system is performing from moment to moment and can help you figure out what might be slowing it down.

Another aspect of system administration is solving problems. Linux includes several tools that can help you track down system problems. One of the most important of these tools is syslogd, the system log daemon. Using /etc/syslogd.conf, you can control which error messages appear on the console, which are sent as email, and which go to one of several log files.