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EPAIR(4)		     Kernel Interfaces Manual			EPAIR(4)

NAME
     epair -- A pair of virtual back-to-back connected Ethernet interfaces

SYNOPSIS
     To compile this driver into the kernel, place the following line in your
     kernel configuration file:

	   device epair

     Alternatively, to load the driver as a module at boot time, place the
     following line in loader.conf(5):

	   if_epair_load="YES"

DESCRIPTION
     The  epair  is  a pair of Ethernet-like software interfaces, which are con-
     nected back-to-back with a virtual cross-over cable.

     Each epair interface pair is created at runtime  using  interface	cloning.
     This  is  most easily done with the ifconfig(8) create command or using the
     cloned_interfaces variable in rc.conf(5).	While for cloning you only  give
     either  epair  or	epair<n> the epair pair will be named like epair<n>[ab].
     This means the names of the first epair  interfaces  will	be  epair0a  and
     epair0b.

     Like  any	other  Ethernet  interface, an epair needs to have a network ad-
     dress.  Each epair will be assigned a locally administered address  by  de-
     fault,  that  is only guaranteed to be unique within one network stack.  To
     change the default addresses one may use the SIOCSIFADDR ioctl(2) or ifcon-
     fig(8) utility.

     The basic intent is to provide connectivity  between  two	virtual  network
     stack  instances.	When connected to an if_bridge(4), one end of the inter-
     face pair can also be part of another (virtual) LAN.   As	with  any  other
     Ethernet interface, epair can have a vlan(4) configured on top of it.

SEE ALSO
     ioctl(2),	 altq(4),   bpf(4),   if_bridge(4),   vlan(4),	 loader.conf(5),
     rc.conf(5), ifconfig(8)

HISTORY
     The epair interface first appeared in FreeBSD 8.0.

AUTHORS
     The epair interface was written by Bjoern A. Zeeb, CK Software GmbH,  under
     sponsorship from the FreeBSD Foundation.

FreeBSD 14.2			 March 18, 2015 			EPAIR(4)

Want to link to this manual page? Use this URL:
<https://man.freebsd.org/cgi/man.cgi?query=epair&manpath=FreeBSD+14.2-RELEASE+and+Ports>

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