[nsp] Transparent bridging over E1 WAN link

[Andre Beck]

Hi,

On Mon, Jul 19, 2004 at 11:41:38AM +0100, Fernando Catalão wrote:
> 
> I have tried this example but to no avail. I am trying to bridge sub-interface 20 site 1 to sub-interface 10 site 2.
> 
> 
> ----------7206 site 1------------
> bridge 10 irb
> bridge 10 protocol ieee
> bridge 10 route ip
>  
> int fe0/0.10
>   bridge 10 
> 
> int s0/0
>   ip add t.t.t.1
>   bridge 10
> ----------------------------------

Hmm. I'm not seeing a BVI anywhere. Further, having both IP and a bridge
group on the same interface is probably well with CRB, but not with IRB.
But I'm not entirely sure, mainly because bridging is often broken in
some way on Cisco Routers and docs on it are cluttered up with strange
wording and nonsense explanations that don't make things any clearer
(just try to find out what "bridge x route ip" is actually good for
and you'll understand - already the command is nonsense [when I have
a BVI on that bridge group and it has IP configured, isn't that as
explicit a statement that I want to route IP as it could be?], but
the explanation makes it really dark).

BTW, what encaps are you running on the serials? There's some chance that
this will require an encapsulation able to do IP and remote bridging at
the same time - I prefer PPP in such cases (can concurrently run IPCP
and BridgeCP "on top of" LCP).

> ----------7206 site 2------------
> bridge 10 irb
> bridge 10 protocol ieee
> bridge 10 route ip
>  
> int e0/0.10
>   bridge 10 
> 
> int s0/0
>   ip add t.t.t.2
>   bridge 10
> ----------------------------------

I'd first try rewriting this to the two serials beeing purely bridged.
For the IP routing, establish a BVI on each end. Alternatively, convert
it to CRB, which is what you are trying to configure IMO, anyway.

If this still doesn't work, have a look on your IOS version. I was in
bridging hell lately trying to do IRB on ATM ptp subifs on a 7206
running 12.0S, which broke badly. I've then got word that in 12.0S,
bridging might be configurable, but is not tested. Forces me to
12.2S with route-bridge encapsulation. On the other hand, I've got
setups of 1603's doing CRB (IP routing and LAT bridging) perfectly,
so it can work if all is well. In that cases, the boxes were running
not too old IOS main line versions.

-- 
                  The _S_anta _C_laus _O_peration
  or "how to turn a complete illusion into a neverending money source"

-> Andre Beck    +++ ABP-RIPE +++    IBH Prof. Dr. Horn GmbH, Dresden <-