Interface Control Scripts

The interface control scripts control activating and deactivating interface connections. There are two primary interface control scripts, /sbin/ifdown and /sbin/ifup, that call on control scripts located in the /etc/sysconfig/network-scripts/ directory.

The two primary interface control scripts in the /etc/sysconfig/network-scripts directory, ifdown and ifup, are symbolic links to the scripts in the /sbin/ directory. When either of these scripts are called, they accept a value of the interface to be used, such as:

ifup eth0
Determining IP information for eth0... done. 

At that point, the /etc/sysconfig/network-scripts/network-functions and /etc/rc.d/init.d/functions files are used to perform a variety of tasks. See the Section called Network Functions for more information about these tasks.

After verifying that an interface has been specified and that the user executing the request is allowed to bring the interface up or down, the correct script for the type of interface device brings the interface up or down. The following interface control scripts are the most common:

Be aware that removing or modifying any scripts in the /etc/sysconfig/network-scripts/ directory can cause interface connections to act strangely or fail, as these scripts. Only advanced users should modify scripts related to a network interface.

You can also use the init script /etc/rc.d/init.d/network to activate and deactive all network interfaces configured to start at boot time with the command:

/sbin/service network action

Where action is either start, stop, or restart. You can also use the command /sbin/service/network status to view a list of configured devices and currently active devices.