Translational Bridging between Token Ring and Ethernet, IRB, and Various Routing Protocols

From: crl (cisco@xxxxxxxxxxxx)
Date: Fri Apr 27 2001 - 13:13:21 GMT-3


   
Doing some experiments. Topology is:

r4---token-ring---r3---ethernet---r2

On r3, I'm doing SR/TLB and IRB. The Token Ring and Ethernet are a common,
bridged subnet, and r3 has other interfaces that are routed (serials) but I
don't think they're relvant to this discussion.

Experimenting with various routing protocols on this network segment. I
found that RIP1, RIP2, and IGRP work well in this situation. OSPF and EIGRP
do not establish adjacencies. I have the bitswap-layer3-addresses command in
place to allow ping, telnet etc to work well between all three routers.

Take OSPF for example.
r4#sh ip ospf nei
<no output>

r3#sh ip ospf nei
Neighbor ID Pri State Dead Time Address Interface
197.7.77.1 1 INIT/DROTHER 00:00:35 197.7.8.4 BVI1
197.7.8.10 1 FULL/DR 00:00:33 197.7.8.10 BVI1

r2#sh ip ospf nei
Neighbor ID Pri State Dead Time Address Interface
197.7.77.1 1 INIT/DROTHER 00:00:39 197.7.8.4 Ethernet0
197.7.8.3 1 FULL/BDR 00:00:31 197.7.8.3 Ethernet0

Doesn't seem to make much sense. I suspected it was a multicast issue, but
RIP2 works well. It's not an MTU problem, I checked that out - everything is
set to 1500. I suspect the bitswap-layer3 command might be mangling EIGRP
and/or OSPF, but not RIP and IGRP.

Here's the relevant configs. I'd just like to know if this is impossible
(great!) or if I'm missing something (doh!):

r4#sh run
!
 interface Loopback0
 ip address 197.7.77.1 255.255.255.0
 no ip directed-broadcast
!
interface TokenRing0
 mtu 1500
 ip address 197.7.6.4 255.255.255.0 secondary
 ip address 197.7.8.4 255.255.255.0
 no ip directed-broadcast
 ip nat outside
 ring-speed 16
!
router ospf 1
 network 197.7.0.0 0.0.255.255 area 0

-------------------------------------------

r3#sh run
!
bridge irb
!
interface Ethernet0
 no ip address
 no ip directed-broadcast
 bridge-group 1
!
interface Serial1
 ip address 197.7.7.3 255.255.255.0
 no ip directed-broadcast
!
interface TokenRing0
 mtu 1500
 no ip address
 no ip directed-broadcast
 ring-speed 16
 bridge-group 1
!
interface BVI1
 ip address 197.7.8.3 255.255.255.0
 no ip directed-broadcast
!
router ospf 1
 network 197.7.0.0 0.0.255.255 area 0
!
bridge 1 protocol ieee
bridge 1 bitswap-layer3-addresses
 bridge 1 route ip

-------------------------------------------

r2#sh run
!
 interface Ethernet0
 ip address 197.7.8.10 255.255.255.0
!
!
router ospf 1
 network 197.7.0.0 0.0.255.255 area 0
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