Network Administration: Linux Network Configuration Files

Like other operating system services, the Linux network is configured by settings that are specified in configuration files that you can find in the /etc directory or in one of its subdirectories. Graphical configuration programs such as Red Hat Network Configuration are actually little more than glorified text editors that enable you to select network configuration options from user-friendly screens and then save your configuration changes to the standard configuration files.

If you prefer to do the grunt work yourself, you can open the configuration files in a text editor and make changes to them directly.

Any time you open a configuration file in a text editor, you run the risk of messing up your system’s configuration. So be careful!

The following table lists the main Linux network configuration files and describes what each file does.

Linux Network Configuration Files
File Location Description
network /etc/sysconfig Basic network configuration.
hostname /etc Specifies the host name (obsolete, but should still be
present).
ifcfg-eth0 -/etc/sysconfig/ IP settings for the first Ethernet adapter
network-scripts.
ifcfg-eth1 -/etc/sysconfig/ IP settings for the second Ethernet adapter
network-scripts.
hosts /etc Lists host address mappings.
resolv.conf /etc Lists DNS nameservers.
nsswitch.conf /etc Specifies the name search order.
xinetd.conf /etc Specifies which network services are started
automatically.