RE: [nsp] 6509s, BGP, dot1q, Static Routes limit, and such things

From: Rubens Kuhl Jr. (
Date: Thu May 31 2001 - 20:14:56 EDT

6509, Sup1a/Sup2, both running the new MSFC2, has no problem dealing with a
lot of static routes, BGP and other L3 features you might want.

Some gotchas on 6509 you should look at:
1) Sup1a+MSFC2 uses MLS-driven L3 switching, which can be easily crack down
if you turn full-flow (IP src/dst, L4 src/dst info) on or use something that
requires it (such as Server Load Balancing), because of 32k suggested
simultaneous flows, 128K upper limit. Running it at dest-flow (IP dst only)
will work if your site isn't popular enough to have more than 32K different
IPs at the simultaneous sessions; Sup2 is strongly suggested to such
scenarios, or if you can spend the extra dollars before you have the demand.
Sup2 uses CEF-driven L3 switching and doesn't suffer from this.
2) Backplane performance without switch fabric is a bit limited compared to
BlackDiamond. Using switch fabric and only fabric-enabled modules (only
gigabit modules available) provides lots of bandwidth to play with, but also
requires Sup2.

Rubens Kuhl Jr.

-----Original Message-----
From: Karyn Ulriksen []
Sent: Thursday, May 31, 2001 6:32 PM
Subject: [nsp] 6509s, BGP, dot1q, Static Routes limit, and such things

We've been using Cisco on our WAN and for customer access router forever,
but at our core and edge we've used many other switches. Currently, we are
using Extreme Networks' BlackDiamond at our core and we are looking to
replace it with a 6509. We had been thinking about it for a while since we
are using the older chipset on the BlackDiamond and upgrading the switch to
BGP was a few dollars. However, now we ran into Exteme's limitation of 64
static routes per route processor card (we have two, so 128 static routes).
Which is definitely a show stopper unless we can get all of our colos to
load OSPF... right.

Anyways, I've been did my homework on these, BUT I know that its a new
switch and I want to see if anybody saw gotchas before I get stretched on
the rack for opening the company coffers to the tune of 80G's. Also, if
anybody has info/comments on the Supervisor Ia versus the II, I'd like to
hear them.


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