16.2.4. Alias and Clone Files
Two lesser-used types of interface configuration files are alias and clone files.
Alias interface configuration files, which are used to bind multiple addresses to a single interface, use the
For example, an
ifcfg-eth0:0file could be configured to specify
DEVICE=eth0:0and a static
10.0.0.2, serving as an alias of an Ethernet interface already configured to receive its
ifcfg-eth0. Under this configuration,
eth0is bound to a dynamic
IPaddress, but the same physical network card can receive requests via the fixed,
Alias interfaces do not support
A clone interface configuration file should use the following naming convention:
ifcfg-<if-name>-<clone-name>. While an alias file allows multiple addresses for an existing interface, a clone file is used to specify additional options for an interface. For example, a standard
DHCPEthernet interface called
eth0, may look similar to this:
DEVICE=eth0 ONBOOT=yes BOOTPROTO=dhcp
Since the default value for the
noif it is not specified, users cannot bring this interface up and down. To give users the ability to control the interface, create a clone by copying
ifcfg-eth0-userand add the following line to
This way a user can bring up the
eth0interface using the
/sbin/ifup eth0-usercommand because the configuration options from
ifcfg-eth0-userare combined. While this is a very basic example, this method can be used with a variety of options and interfaces.
The easiest way to create alias and clone interface configuration files is to use the graphical Network Administration Tool. For more information on using this tool, refer to Chapter 17, Network Configuration.