Chapter 8. Network Interfaces
/etc/sysconfig/network-scripts/directory. Although the number and type of interface files can differ from system to system, there are three categories of files that exist in this directory:
- Interface configuration files
- Interface control scripts
- Network function files
8.1. Network Configuration Files
/etc/hosts— The main purpose of this file is to resolve hostnames that cannot be resolved any other way. It can also be used to resolve hostnames on small networks with no DNS server. Regardless of the type of network the computer is on, this file should contain a line specifying the IP address of the loopback device (
localhost.localdomain. For more information, refer to the
/etc/resolv.conf— This file specifies the IP addresses of DNS servers and the search domain. Unless configured to do otherwise, the network initialization scripts populate this file. For more information about this file, refer to the
/etc/sysconfig/network— Specifies routing and host information for all network interfaces. For more information about this file and the directives it accepts, refer to Section 4.1.25, “
/etc/sysconfig/network-scripts/ifcfg-<interface-name>— For each network interface, there is a corresponding interface configuration script. Each of these files provide information specific to a particular network interface. Refer to Section 8.2, “Interface Configuration Files” for more information on this type of file and the directives it accepts.
/etc/sysconfig/networking/directory is used by the Network Administration Tool (
system-config-network) and its contents should not be edited manually. In addition, any use of the Network Administration Tool, even launching the application, will override any directives previously set in
/etc/sysconfig/network-scripts. Using only one method for network configuration is strongly encouraged, due to the risk of configuration deletion.