7600 on the edge Was: Re: [nsp] Catalyst 5000(5500) over 4000(4500)???

[sthaug at nethelp.no]

> Any *real life* experience running 7600 as a border router with a couple of
> full BGP feeds (with SupII/MSFC2/PFC2)? Please? :) For the simplicity let's
> say that we're happy with available interfaces performance/features.

Sure. We're currently running two 6500 (SupII/MSFC2/PFC2, no OSMs) as 
border routers. Memory usage from one of them with 3 full BGP views and
several partial:

                Head    Total(b)     Used(b)     Free(b)   Lowest(b)  Largest(b)
Processor   41E41560   469494432   178717736   290776696   278908456   181201892
      I/O    DE00000    35651584     8769648    26881936    26311760    26538812

You really want 512 MB on the MSFC2 (though you can get by *for now*
with 256 MB). This box is running 12.1(13)E, with 30 weeks uptime. We
also have several boxes with 12.1(13)E1.

No unicast RPF checking due to the size of a full routing table (this
has been discussed before). On the other hand 6500/7600 is very happy 
to run ACLs in hardware, so you can get most of the uRPF protection 
that way.

We had a 4 port STM-1 OSM that we used for a full BGP feed on another
6500. This box was somewhat unstable - probably because it was running
a much earlier version of 12.1E, in combination with being a VTP master.
We're moving away from VTP on all our native IOS 6500s. (You need VTP
transparent mode in any case - on order to handle VLANs above 1005, and
to handle redundant supervisors.)

We're very happy with our 6500s as border routers. We're trying to move
all our peerings to Ethernet, and thus see no need for OSMs on these
boxes. (We have OSMs on other 7600s because we need them for MPLS VPNs.
However, due to the exorbitant price of OSMs we're trying to limit our
OSM usage to the absolute minimum. We're looking forward to Sup720 which
will be able to do MPLS without OSMs)

Steinar Haug, Nethelp consulting, sthaug at nethelp.no