5fc175b7b4
The name trunk is misused as the networking term trunk means carrying multiple VLANs over a single connection. The IEEE standard for link aggregation (802.3 section 3) does not talk about 'trunk' at all while it is used throughout IEEE 802.1Q in describing vlans. The lagg(4) driver provides link aggregation, failover and fault tolerance. Discussed on: current@
173 lines
5.2 KiB
Groff
173 lines
5.2 KiB
Groff
.\" $OpenBSD: trunk.4,v 1.18 2006/06/09 13:53:34 jmc Exp $
|
|
.\"
|
|
.\" Copyright (c) 2005, 2006 Reyk Floeter <reyk@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.
|
|
.\"
|
|
.\" $FreeBSD$
|
|
.\"
|
|
.Dd April 10, 2007
|
|
.Dt LAGG 4
|
|
.Os
|
|
.Sh NAME
|
|
.Nm lagg
|
|
.Nd link aggregation and link failover interface
|
|
.Sh SYNOPSIS
|
|
To compile this driver into the kernel,
|
|
place the following line in your
|
|
kernel configuration file:
|
|
.Bd -ragged -offset indent
|
|
.Cd "device lagg"
|
|
.Ed
|
|
.Pp
|
|
Alternatively, to load the driver as a
|
|
module at boot time, place the following line in
|
|
.Xr loader.conf 5 :
|
|
.Bd -literal -offset indent
|
|
if_lagg_load="YES"
|
|
.Ed
|
|
.Sh DESCRIPTION
|
|
The
|
|
.Nm
|
|
interface allows aggregation of multiple network interfaces as one virtual
|
|
.Nm
|
|
interface for the purpose of providing fault-tolerance and high-speed links.
|
|
.Pp
|
|
A
|
|
.Nm
|
|
interface can be created using the
|
|
.Ic ifconfig lagg Ns Ar N Ic create
|
|
command.
|
|
It can use different link aggregation protocols specified
|
|
using the
|
|
.Ic laggproto Ar proto
|
|
option.
|
|
Child interfaces can be added using the
|
|
.Ic laggport Ar child-iface
|
|
option and removed using the
|
|
.Ic -laggport Ar child-iface
|
|
option.
|
|
.Pp
|
|
The driver currently supports the aggregation protocols
|
|
.Ic failover
|
|
(the default),
|
|
.Ic fec ,
|
|
.Ic lacp ,
|
|
.Ic loadbalance ,
|
|
.Ic roundrobin ,
|
|
and
|
|
.Ic none .
|
|
The protocols determine which ports are used for outgoing traffic
|
|
and whether a specific port accepts incoming traffic.
|
|
The interface link state is used to validate if the port is active or
|
|
not.
|
|
.Bl -tag -width loadbalance
|
|
.It Ic failover
|
|
Sends and receives traffic only through the master port.
|
|
If the master port becomes unavailable,
|
|
the next active port is used.
|
|
The first interface added is the master port;
|
|
any interfaces added after that are used as failover devices.
|
|
.It Ic fec
|
|
Supports Cisco EtherChannel.
|
|
This is a static setup and does not negotiate aggregation with the peer or
|
|
exchange frames to monitor the link.
|
|
.It Ic lacp
|
|
Supports the IEEE 802.3ad Link Aggregation Control Protocol (LACP) and the
|
|
Marker Protocol.
|
|
LACP will negotiate a set of aggregable links with the peer in to one or more
|
|
Link Aggregated Groups.
|
|
Each LAG is composed of ports of the same speed, set to full-duplex operation.
|
|
The traffic will be balanced across the ports in the LAG with the greatest
|
|
total speed, in most cases there will only be one LAG which contains all ports.
|
|
In the event of changes in physical connectivity, Link Aggregation will quickly
|
|
converge to a new configuration.
|
|
.It Ic loadbalance
|
|
Balances outgoing traffic across the active ports based on hashed
|
|
protocol header information and accepts incoming traffic from
|
|
any active port.
|
|
This is a static setup and does not negotiate aggregation with the peer or
|
|
exchange frames to monitor the link.
|
|
The hash includes the Ethernet source and destination address, and, if
|
|
available, the VLAN tag, and the IP source and destination address.
|
|
.It Ic roundrobin
|
|
Distributes outgoing traffic using a round-robin scheduler
|
|
through all active ports and accepts incoming traffic from
|
|
any active port.
|
|
.It Ic none
|
|
This protocol is intended to do nothing: it disables any traffic without
|
|
disabling the
|
|
.Nm
|
|
interface itself.
|
|
.El
|
|
.Pp
|
|
Each
|
|
.Nm
|
|
interface is created at runtime using interface cloning.
|
|
This is
|
|
most easily done with the
|
|
.Xr ifconfig 8
|
|
.Cm create
|
|
command or using the
|
|
.Va cloned_interfaces
|
|
variable in
|
|
.Xr rc.conf 5 .
|
|
.Sh EXAMPLES
|
|
Create a 802.3ad link aggregation using LACP with two
|
|
.Xr bge 4
|
|
Gigabit Ethernet interfaces:
|
|
.Bd -literal -offset indent
|
|
# ifconfig bge0 up
|
|
# ifconfig bge1 up
|
|
# ifconfig lagg0 laggproto lacp laggport bge0 laggport bge1 \e
|
|
192.168.1.1 netmask 255.255.255.0
|
|
.Ed
|
|
.Pp
|
|
The following example uses an active failover interface to set up roaming
|
|
between wired and wireless networks using two network devices.
|
|
Whenever the wired master interface is unplugged, the wireless failover
|
|
device will be used:
|
|
.Bd -literal -offset indent
|
|
# ifconfig em0 up
|
|
# ifconfig ath0 nwid my_net up
|
|
# ifconfig lagg0 laggproto failover laggport em0 laggport ath0 \e
|
|
192.168.1.1 netmask 255.255.255.0
|
|
.Ed
|
|
.Sh SEE ALSO
|
|
.Xr ng_fec 4 ,
|
|
.Xr ng_one2many 4 ,
|
|
.Xr ifconfig 8
|
|
.Sh HISTORY
|
|
The
|
|
.Nm
|
|
device first appeared in
|
|
.Fx 7.0 .
|
|
.Sh AUTHORS
|
|
.An -nosplit
|
|
The
|
|
.Nm
|
|
driver was written by
|
|
.An Reyk Floeter Aq reyk@openbsd.org .
|
|
The LACP implementation was written by
|
|
.An YAMAMOTO Takashi
|
|
for
|
|
.Nx .
|
|
.Sh BUGS
|
|
There is no way to configure LACP administrative variables, including system
|
|
and port priorities.
|
|
The current implementation always performs active-mode LACP and uses 0x8000 as
|
|
system and port priorities.
|
|
.Pp
|
|
WPA security does not currently work correctly with a wireless interface added
|
|
to the lagg port.
|