vlan taggging on etherchannel

[Shteryana Shopova]

On 8/21/07, Tom Judge <tom at tomjudge.com> wrote:
> Arne Schwabe wrote:
> > Tom Judge schrieb:
> >> Mohacsi Janos wrote:
> >>> Dear All,
> >>>     What is the recommended way to configure vlan interfaces on
> >>> etherchannel bonded interfaces in a failure mode. I found, that
> >>> etherchannel is supported by ng_fec(4) (but not exactly what I want)
> >>> and also found that there two? way of configuring vlans: vlan(4) and
> >>> ng_vlan(4). But I did not found any description or configuration
> >>> snippet to configure both preferentially via /etc/rc.conf neither in
> >>> FreeBSD 6.x-stable, neither in FreeBSD-7.0-current. What I want to
> >>> achieve:
> >>>
> >>>   [switch1]-----GE---bge0----\    /----vlan100
> >>>                               }=={-----vlan101
> >>>   [switch2]-----FE---bge1----/    \----vlan102
> >>>                                    \---vlan103
> >>>
> >>>
> >>> I would like to  prefer all the vlans via bge0 with GE towards
> >>> switch1. And use only bge1 in case of switch1 or bge0 link failure.
> >>>
> >>> I could use bond on Linux for this purpose. How to achieve similar
> >>> setup?
> >>>
> >>
> >> You may want to take a look at if_lagg, it supports EtherChannel (AKA
> >> fec), LACP and failover modes (Which is what you would need).  It is
> >> available in RELENG_6 and Current.
> > If the switches don't support LACP/Fec over two devices use bridge_stp
> > to simulate a switche and let spanning-tree do the failover.
> >
> > Arne
>
> Spanning tree may not select the GigE connection as the primary
> connection and use the FastE connection instead. if_lagg with

That is not correct in the default case - STP caluculates the pathcost
for a link based on its speed. Also one can always force a better
priority for a link using ifconfig(8) on FreeBSD.

I'd recommend reading
http://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/network-bridging.html
to start with. Also freebsd-net@ might be a better place for asking
networking related questions. :)

cheers,
Shteryana