Two-Minute Drill

Here are some of the key points from the certification objectives in Chapter 7.

Network Configuration

❑	Key network configuration files are in the /etc/sysconfig directory: the network file, and the networking and network-scripts subdirectories.
❑	You can start the Network Configuration utility with the system-config-network command.
❑	To manage network settings on each interface, use dhclient, ifup, and ifdown.
❑	The ifconfig command is used to configure and display network devices.
❑	Use ifup eth0 and ifdown eth0 to activate and deactivate the eth0 interface.
❑	The netstat command is used to display a plethora of network connectivity information; route -n is another way to check the current routing table.
❑	The arp command is used to view or modify the local hardware address database.

The CUPS Printing System

❑	The Printer Configuration tool, which you can start with the system-config-printer command, can be used to configure most popular printers in /etc/cups/cupsd.conf.
❑	CUPS provides a Web-based interface. Once enabled, you can get to this interface in your browser by navigating to http://localhost:631.

Automating System Administration: cron and At

❑	The cron system allows any user to schedule jobs so they run at given intervals.
❑	The at system allows users to configure jobs to run once at a scheduled time.
❑	The crontab command is used to work with cron files. Use crontab -e to edit, crontab -l to list, or crontab -d to delete cron files.
❑	The /etc/cron.allow and /etc/cron.deny files are used to control access to the cron job scheduler.

Understanding, Maintaining, and Monitoring System Logs

❑	Red Hat Enterprise Linux includes two logging daemons: klogd for kernel messages and syslogd for all other process activity. Both are activated by the /etc/init.d/syslog service script.
❑	You can use log files generated by the syslogd daemon to track activities on your system.
❑	Most log files are stored in /var/log.
❑	You can configure what is logged through the syslog configuration file, /etc/ syslog.conf.