.\"	$NetBSD: vether.4,v 1.6 2024/09/26 09:59:56 roy Exp $
.\"
.\"	$OpenBSD: vether.4,v 1.5 2017/10/17 22:47:58 schwarze Exp $
.\"
.\" Copyright (c) 2009 Theo de Raadt <deraadt@openbsd.org>
.\"
.\" Permission to use, copy, modify, and distribute this software for any
.\" purpose with or without fee is hereby granted, provided that the above
.\" copyright notice and this permission notice appear in all copies.
.\"
.\" THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
.\" WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
.\" MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
.\" ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
.\" WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
.\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
.\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
.\"
.Dd September 26, 2017
.Dt VETHER 4
.Os
.Sh NAME
.Nm vether
.Nd virtual Ethernet interface
.Sh SYNOPSIS
.Cd "pseudo-device vether"
.Sh DESCRIPTION
The
.Nm
interface simulates a normal Ethernet interface by encapsulating
standard network frames with an Ethernet header, specifically
for use as a member in a
.Xr bridge 4 .
.Pp
To use
.Nm
the administrator needs to configure an address onto the interface
so that packets can be routed to it.
An Ethernet header will be prepended and, if the
.Nm
interface is a member of a
.Xr bridge 4 ,
the frame will show up there.
.Pp
The
.Nm
link state can be controlled using
.Xr ifconfig 8 :
.Pp
.Bl -tag -offset indent -width Cm -compact
.It Cm media auto
link state
.Dq up
.It Cm media none
link state
.Dq down
.El
.Sh SEE ALSO
.Xr bridge 4 ,
.Xr ifconfig 8
.Sh HISTORY
The
.Nm
interface first appeared in
.Ox 4.7
and
.Nx 10 .
.Sh AUTHORS
.An Theo de Raadt Aq Mt deraadt@openbsd.org
.Sh BUGS
Like
.Xr tap 4 ,
the Ethernet address chosen will be partially random, and may
occasionally collide with another address.