nanog mailing list archives
Re: Single IP routing problems through Level3
From: Matthew Kaufman <matthew () eeph com>
Date: Sun, 15 Jun 2008 15:07:21 -0700
Matt Palmer wrote:
A multiple-link bundle which is load balanced by source/destination pair with an undetected dud link? I hadn't thought of that, but it does make an *awful* lot of sense....
I've also seen interesting OSPF misconfigurations that resulted in a router doing path-wise load balancing between the live link and an unroutable destination address that went into the bit bucket.
On the Cisco boxes I was using at the time, the hallmark of load-balancing into a dead path was that every other IP address worked, but then every some number of addresses (12, as I remember, but I'm not 100% sure) the polarity flipped, so that whichever of odd vs even had worked before was now the one that didn't for the next N addresses. Artifact of the hash algorithm in use, no doubt.
Matthew Kaufman matthew () eeph com http://www.matthew.at
Current thread:
- Single IP routing problems through Level3 Matt Palmer (Jun 15)
- Re: Single IP routing problems through Level3 Rubens Kuhl Jr. (Jun 15)
- Re: Single IP routing problems through Level3 Matt Palmer (Jun 15)
- Re: Single IP routing problems through Level3 Matthew Kaufman (Jun 15)
- Re: Single IP routing problems through Level3 Matt Palmer (Jun 15)
- Re: Single IP routing problems through Level3 Tim Peiffer (Jun 15)
- <Possible follow-ups>
- Re: Single IP routing problems through Level3 Jon Wolberg (Jun 15)
- Re: Single IP routing problems through Level3 Rubens Kuhl Jr. (Jun 15)