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2948GL3 IRB appletalk

I think I know the answer to this, but I wanted to see if anyone had a better way to do this. We have a 6513 at the core of the network that does routing for all gigabit uplinks. We also have a complex of 12 buildings across the campus. Each of the 12 buildings has a fiber pair that runs back to a single building in the complex. There is a 100FX to 100TX transceiver at each end so that each of the 12 connections can connect to the 2948GL3. That main building has a 2948GL3 switch with a gigabit uplink back to the core. There is a single pair of fiber run to that building from the core of the network.

We need to be able to support IP, IPX, and Appletalk at those 12 remote buildings. We wanted to use the 2948GL3 to route these protocols, but I am afraid that with the appletalk requirement, we will just have to bridge all the ports into a BVI. Is there a better way to do this? ideally, I would like to be able to have a routed port on the 2948GL3 connect to each of the 12 remote buildings. If I do this I should be able to route the IP and IPX across them, but I think that the Appletalk would be stopped at that routed interface and the macs from those 12 buildings could not communicate using appletalk with the other macs on campus.

I looked at IRB, but it sounds like this would not allow me to route IP and IPX across the interfaces and still allow appletalk to be bridged across all of the interfaces. I am planning on just setting up a single BVI and assigning all the ports to it and bridging the whole thing back to the 6513 at the core. All 12 buildings would be in a single subnet.

If anyone has a better way to do this, I would be eager to try it!


Josh Krueger


Re: 2948GL3 IRB appletalk

IRB is specifically designed to allow you to route certain protocols on an interface while simultaneously bridge other protocols on the same interface/s. I do not see why this might not work unless you have seen a document that explicitly states that the normal operation of IRB is not applicable to AppleTalk.

You could bridge AppleTalk, bridge and/or route IPX, and route IP in the same bridge group. IRB bridges everything by default, so you would to configure bridge route command to both bridge and route the appropriate protocol (IP, IPX, AT). Use the no bridge bridge command to disable bridging.

Refer for Config details.

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