Chapter 8. Network Interfaces

Under Red Hat Enterprise Linux, all network communications occur between configured software interfaces and physical networking devices connected to the system.

The configuration files for network interfaces, and the scripts used to activate and deactivate them, are located in the /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:

The files in each of these categories work together to enable various network devices.

This chapter explores the relationship between these files and how they are used.

8.1. Network Configuration Files

Before delving into the interface configuration files, let us first itemize the primary configuration files used in network configuration. Understanding the role these files play in setting up the network stack can be helpful when customizing a Red Hat Enterprise Linux system.

The primary network configuration files are as follows:


The /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.

For more information about configuring network interfaces using the Network Administration Tool, refer to the chapter titled Network Configuration in the Red Hat Enterprise Linux System Administration Guide.