linux and intervlan routing

[mailings02 at ttlexceeded.com (Bob George)]

Bill Holt wrote:
> [...]
> I know of freesco. I know of vlan support as of 2.4. What I
don't
> know is a.) does freesco support 802.1q? (I'm not interested in
> proprietary ISL or VLT etc.) I know freesco supports multiple
virtual
> adresses.

I've used 802.1q VLAN trunking on Linux (2.4 kernel) but not
Freesco specifically. I would assume it'd work with the
appropriate reconfiguration.

> I couldn't find any good documentation on linux as a
> router. What I'm going to do is use 2 nics, one to the dsl the
other
> as the router on a stick. Get one nic to pass traffic to and
from the
> internet (I smell NAT) and use the second nic to route between
three
> vlans over 3com switches (supporting 802.1q).

As long as the 3com switches themselves support 802.1q, it should
work fine. I had one physical interface on my linux box break out
a half-dozen VLANs on a 24 port Cisco Cat2924 switch, and it
worked quite well.

Just watch out for changes on max MTU etc. associated with 802.1q.
Exact configuration varies by distribution, but I fumbled around
with Mandrake 9.2 and have it working well enough. Rolling your
own init script might be easier though.

- Bob