[88217] in North American Network Operators' Group
Re: Split flows across Domains
daemon@ATHENA.MIT.EDU (Simon Leinen)
Wed Jan 25 11:18:45 2006
To: "Robert E.Seastrom" <rs@seastrom.com>
Cc: Joe Abley <jabley@isc.org>,
"Christopher L. Morrow" <christopher.morrow@verizonbusiness.com>,
Glen Kent <glen.kent@gmail.com>, NANOG list <nanog@merit.edu>
From: Simon Leinen <simon@limmat.switch.ch>
In-Reply-To: <87fynd7b23.fsf@valhalla.seastrom.com> (Robert E. Seastrom's
message of "Tue, 24 Jan 2006 13:09:08 -0500")
Date: Wed, 25 Jan 2006 17:15:26 +0100
Errors-To: owner-nanog@merit.edu
Robert E Seastrom writes:
> Yes and no. CEF is {src, dst} hash IIRC, and "per-flow" usually
> means {src, srcport, dst, dstport, [proto, tos]} hash in my
> experience.
Correct.
The Catalyst 6500/7600 OSR with Sup2/Sup32/Sup720 can be configured to
hash based on L4 ports in addition to the IP addresses (for IPv4):
http://puck.nether.net/pipermail/cisco-nsp/2005-December/026952.html
This is handy when you have multiple "striped" TCP connections between
a single pair of hosts, and want them to be able to use multiple
equal-cost paths, but still want to avoid reordering inside each
connection (as you would inevitably get with per-packet load
sharing).
--
Simon.
