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Is it possible to use bridged/teamed NIC's on a server to connect two switches together?

I have a server with Two NIC ports: Port 1, Port 2. I bridged them using Windows (Server 2008 R2 Enterprise, if it matters). I have two 48 port HP Procurve switches (Switch 1 and Switch 2). I plugged Port 1 into Switch1, and port two into Switch2. Would this method, without a link between the two switches, other than the server's bridged NIC ports, allow communication between switches? It seems possible, but i was unsure if the server would allow traffic to hosts other than itself to passthrough destined for a device (such as the router) on the other switch.
If this is possible, please specify how; such as advanced NIC settings, etc.
Thanks in advance.
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1 Solution
Well, the first question is why?  Why not use a crossover cable between the switches or its uplink port.  

But, ignoring that -- you can set the Server up to route between the two, but each switch would be a separate subnet, and you'd use the Routing and Remote Access server to set this up -- I've never tried it with bridging.  That's one option.  I don't think bridging would quite work the way you're thinking.
mhdcommunicationsAuthor Commented:
I do NOT want to do it this way, the reason im asking is because it IS working this way, and it shouldnt. No special routing was setup, nothing. It was NOT working this way before; i had a link between the two switches. I recently (today) removed/added VLAN ports on each switch (just expanding VLAN 1, and decreasing VLAN2) and after that, the link between the switches has not been needed, and the only thing 'connecting' the switches together is Port 1 and Port 2 from the server NIC plugged into Switch 1 and Switch 2 (respectively), but these ports are 'bridged' using Windows.
I also noticed that linking VLAN 2 on Switch 1 and Switch 2 together does not work - it does not allow traffic from one switch to the other.
I am assuming rebooting the switches will fix this, and it's just a glitch from changing VLAN assingments (no, it's not only happening on the ports that had the VLAN assignment changed, it's happening to ALL of them), but that doesnt explain how VLAN 1 on Switch 1 is able to communicate with VLAN 1 on Switch 2, when the only link between the switches is ServerPort 1 into Switch 1, and ServerPort 2 into Switch 2.
The switches are not stacked or connected in any way shape or form other than what i have described, whether physical or software.
Am i missing something?
So, are you wanting to a) make it work like it was, or b) figure out why it's behaving this way?  It sounds like you're more into investigating what's happening, else you'd reboot the switches?

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mhdcommunicationsAuthor Commented:
After rebooting the switches..
Server 2008 R2 (if it matters) with 2 x 10/100/1000 Bridged using Windows
Two HP Procurve 2510G 48-port switches
Port 1-44 on each switch - VLAN 1
Port 45-48 on each switch - VLAN 2

ServerNICPort1 plugged into Switch 1 (VLAN1) and ServerNICPort2 plugged into switch 2 (VLAN1) without a physical link between the switches other than the server, each device on each switch on VLAN1 can communicate. Unplugging one of the server NIC ports halts communication.

On VLAN2, even with a cable link between the switches, it does not allow communication from one switch to another.

Prior to changing the VLAN port assignments, none of this worked like this. I have changed the assignments back, and still have the same issue.
Your first question was if this was possible, and if so, how would you set it up.  However, you then stated you know it's possible/working.  It feels more like a test, as you are *at* the place where your question states you want to get....

a) then, disable bridging if you don't want this occurring.
b) install wireshark and sniff the traffic to confirm it is occurring.
c) clarify?  this seems like a schizophrenic situation.
mhdcommunicationsAuthor Commented:
Yes and no.
I didnt think it was possible, so i asked if it was, and if any special configurations needed to be done: if you had said "yes it's possible, and nothing special needs to be done", i would have my answer, but you stated 'it may be possible, and this is what you need to do - step 1, 2 and exception(s)', so i tested it to check (i needed justification for taking down a 200+ user network for 'tetsing'). If i had stated or implied what my actual situation was, by the power of suggestion, i may have been given a different answer not regarding my actual question.
I dont want to disable bridging on the server for load balancing/fualt tolerance.
it will do as you are experiencing, but I don't see where you get any fault tolerance from unless the only host that both networks need to communicate with is the server that bridges both networks...

If you had two 5400 series switches (2nd gen) you can have LACP trunks that span both switches, or if you had Cisco 3750 switches linked with a stack cable, again you can have LACP trunks that span two switches, with whatyou have at the moment, the server has a single point of failure on two switches.
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