routed versus bridged interface

From: John Conzone (jkconzone@xxxxxxxx)
Date: Sun Sep 03 2000 - 19:14:11 GMT-3


   
       Guys, help me out again. Here's the scenario. I have three
   routers in a row.
   
       R1-----------R2------------R3
   
       On R1, I'm routing IPX on its interface connected to R2, as well
   as running bridging.
       On R2, I only have bridging on both interfaces. No ipx routing.
       On R3, I have IPX routing turned on onthe interface connected to
   R2, and also bridging.
   
       I cannot ping IPX bewteen R1 and R3. They are the same IPX
   network.
       If I configure IRB on R3, remove the IPX network from R3's
   interface, put it on the BVI on R3 and route IPX on the BVI and it
   works. The packets must be getting to R3 either way, but R3 cannot
   decapsulate them when routing directly on the interface becasue he is
   looking for a "routed" packet, but is recieveing a "bridged" packet
   from R2.
       Moving the IPX routing off the interface onto the BVI allows the
   "bridged"packet to be decapsulated and passed to the BVI as a "routed"
   packet.
       Can someone break out what the packet looks like coming out of R1,
   then out of R2 into R3?
       What is it specifically in the packet header , the "bridged"
   packet, that R3 see's when he tries to "route" the packet, that he
   doesn't like. I'm drawing a blank although in my gut I understand
   whats happening.
       I've run into this when binding a virtual interface on a RSP on a
   cat to a lane card, and then sending it to a router. I had to use BVI
   to get the 1483 "bridged" packet to route.
   
   
   



This archive was generated by hypermail 2.1.4 : Thu Jun 13 2002 - 08:24:52 GMT-3