The
ifaliases file specifies the additional addresses (aliases) that each interface has.
ifaliases is processed by
/etc/rc.d/network at system boot time.
Each line of the file is of the form:
address interface [netmask]
The
address is a network address of the alias. This must be a number, or must be in
/etc/hosts, since the nameserver is not running at this point.
The
interface is the network interface the alias will be configured on.
The
netmask is the netmask of the alias' network address. Although this is optional, omitting the netmask is discouraged. Omission results in the use of the classful netmask associated with
address.