[nsp] Catalyst 4507R LAN Edge Routing (BGP)

[rpcbind at speakeasy.net]

> Does anybody have field experience (or 2nd-hand experience) with 
> deploying the 450x in a similar role?  In particular I am curious 
> if the layer3 performance/maturity is as good as the 65xx in a 
> similar configuration with BGP.

I've got both 6000/s2's and 4000/s3's in this role. The performance of the 
sup3 has been fantastic. The one major caveat to watch out for is the 128k fib 
entry limitation -- with a full bgp feed, that should leave you with 
approximately 10% free (and this is relatively static), but could leave you in 
a bind if a provider hoses things and massively deaggregates.

The only real problem I've have with the Sup3 is the 256mb of ram. Moving off 
the original 12.1(8)EW gave some nasty surprises w/ additional memory 
consumption, which left things running very, very tight with 2 ebgp and 1 ibgp 
sessions. Definatley go with the sup4 for the 512mb. Ran into a few crashs 
digging where I shouldn't in 'sh platform', but that's to be expected on a 
brand new release. The move of the 4000-s3/s4 to 12.1E is encouraging in this 
regard.

> Our environment requires BGPv4 (so we'll need the separate InterDomain
> routing license), GigE EtherChannel, and a significant number of
> layer3/4 ACLs, and VLANs.

Be sure to read the docs for details on L4 ACL config. There's several 
limitations that you need to obey to ensure acl processing is kept in 
hardware. If the switch is forced to resort to processor switching, 
performance will be so poor it might as well be dead.

If you're concerned about cost, consider going with the 4006 chassis instead 
of the 450x. Since you obviously aren't concerned about PoE in this role, 
unless you really want the redundnant supervisors, you can save a significant 
amount without compromises.

Be sure to comparison shop against a used 6500-S2/MSFC2. They can be had at
_very_ reasonable prices now (less than a new 4507/S3) and you'll be in that
much better shape still. The only thing I like on 4000's over the 6's is the
option of the over-subscribed 10/100/1000 blades. I prefer a mix of the
WS-X4306 and WS-X4448-GB-RJ45 on the 4000, and wish there was something to
pair up with the WS-X6316 like this on the 6000.

Good luck.