.\"	$NetBSD: ifaliases.5,v 1.14 2008/05/29 14:51:25 mrg Exp $
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.\" Copyright (c) 1996 Matthew R. Green
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.Dd November 17, 2000
.Dt IFALIASES 5
.Os
.Sh NAME
.Nm ifaliases
.Nd interface aliases file
.Sh DESCRIPTION
The
.Nm
file specifies the additional addresses (aliases) that each interface
has.
.Nm
is processed by
.Pa /etc/rc.d/network
at system boot time.
.Pp
Each line of the file is of the form:
.D1 address interface [netmask]
.Pp
The
.Em address
is a network address of the alias.
This must be a number, or must be in
.Pa /etc/hosts ,
since the nameserver is not running at this point.
.Pp
The
.Em interface
is the network interface the alias will be configured on.
.Pp
The
.Em 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
.Em address .
.Sh FILES
.Pa /etc/ifaliases ,
.Pa /etc/rc.d/network
.Sh HISTORY
The
.Nm
file appeared in
.Nx 1.2 .
.Sh BUGS
.Nm
assumes IPv4, and does not support other protocol families.
Please check
.Xr rc.conf 5
for alternatives like
.Pa /etc/ifconfig.xxN .