[Bridge] help setting up a linux bridge with spanning tree to allow multiple vlans accross multiple uplinks

[Marius Karthaus <Marius@Karthaus.nl>]

[-- Attachment #1: Type: text/plain, Size: 1388 bytes --]

For easy reading: http://www.karthaus.nl/r/

Hi,

We used to have 1 single ip range (1.1.1.0/24) that had one uplink to a 
switch of the colocation provider.
Recently we got a second range 2.2.2.0/24 and a redundant uplink 
directly on two routers. But our switch does not have spanning tree 
protocol support so we cannot use them redundantly.
We have set up the switch to have a vlan for both networks like in this 
picture:

http://www.karthaus.nl/r/r1.gif

this way all hosts on the switch can use ips from either network.
However if one of the routers fails, one of the ranges fails. This 
happens quite a lot but this whould not be a problem if we had spanning 
tree that whould allow us to use both uplinks for both networks.
I would like to use a linux box to do this until we can get a switch 
that is capable of stp. I was thinking of something like this:
http://www.karthaus.nl/r/r2.gif

After reading the documentation on linux bridging and stp i'm convinced 
it's possible but i'm not at all sure exactly how to do this. The box 
that i want to use should probably have three NIC's, one for each 
routeruplink and one that connects to our switch. (see the picture). I'm 
guessing that i need to set up multiple bridges each containing a subset 
of the NIC eth0,eth1 and eth2. But this is where i'm confused.
Can anyone show me how to set this up please?

Regards,
M.Karthaus

[-- Attachment #2.1: Type: text/html, Size: 1920 bytes --]

[-- Attachment #2.2: r1.gif --]
[-- Type: image/gif, Size: 3745 bytes --]

[-- Attachment #2.3: r2.gif --]
[-- Type: image/gif, Size: 4659 bytes --]