Copyright (c)2005 YAMAMOTO Takashi,
All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions
are met:
1. Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright
notice, this list of conditions and the following disclaimer in the
documentation and/or other materials provided with the distribution.
THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
SUCH DAMAGE.
------------------------------------------------------------
.Dd February 4, 2005 .Dt AGR 4 .Os ------------------------------------------------------------
.Sh NAME .Nm agr .Nd link aggregation pseudo network interface driver ------------------------------------------------------------
.Sh SYNOPSIS .Cd pseudo-device agr ------------------------------------------------------------
.Sh DESCRIPTION The .Nm driver provides link aggregation functionality. (aka L2 trunking or bonding)
p It supports IEEE 802.3ad Link Aggregation Control Protocol (LACP) and Marker Protocol.
p
The
.Nm
driver supports the following link specific flags for
.Xr ifconfig 8 :
l -tag -width -link0 t Cm link0 Use round-robin distribution algorithm.
Because it violates the frame ordering rule, don't use it unless
you're really sure.
t Cm -link0 Use default distribution algorithm, which is based on the hash of DA/SA,
TCI, and, if available, some upper layer protocol information like
.Xr ip 4
DA/SA.
.El
------------------------------------------------------------
.Sh EXAMPLES
Create an
.Nm
interface,
.Sy agr0 ,
and attach
.Sy re0
and
.Sy re1
to it.
(In other words, aggregate
.Sy re0
and
.Sy re1
so that they can be used as a single interface,
.Sy agr0 )
d -literal -offset indent ifconfig agr0 create
ifconfig agr0 agrport re0
ifconfig agr0 agrport re1
.Ed
p
Destroy an interface created in the above example.
d -literal -offset indent ifconfig agr0 -agrport re0
ifconfig agr0 -agrport re1
ifconfig agr0 destroy
.Ed
------------------------------------------------------------
.Sh SEE ALSO
.Xr ifconfig 8
------------------------------------------------------------
.Sh STANDARDS
IEEE 802.3ad Aggregation of Multiple Link Segments
------------------------------------------------------------
.Sh AUTHORS
The
.Nm
driver was written by
.An YAMAMOTO Takashi .
------------------------------------------------------------
.Sh BUGS
The current implementation of the
.Nm
driver
always attempts automatic configuration via LACP.
There is no way to configure statically or use non IEEE 802.3 devices.
p There is no way to configure LACP administrative variables, including system and port priorities. The current implementation of the .Nm driver always performs active-mode LACP and uses 0x8000 as system and port priorities.
p The .Nm driver uses the MAC address of the first-added physical interface as the MAC address of .Nm interface itself. Thus, removing the physical interface and use it for another purpose can result in non unique MAC addresses.
p The current implementation of the .Nm driver doesn't prevent unsafe operations like some ioctls against underlying physical interfaces. Such operations can result in unexpected behaviours, and are strongly discouraged.
p There is no way to configure .Nm interfaces without attaching physical interfaces.
p Physical interfaces being added to the .Nm interface shouldn't have any addresses except for link level address. Otherwise, the attempt will fail with .Dv EBUSY .