BGP Route Issues
sethm at rollernet.us
Mon Aug 19 03:10:26 UTC 2013
On 8/18/13 6:33 PM, Christopher Karel wrote:
> I'm hoping you guys might be able to offer some advice or insight
> into a BGP problem I've got. I've noticed some strange routes between
> our network, AS27270, and AS22943. It looks like both our networks are
> dual homed. One ISP as the primary, and the other used as a backup,
> with path prepending to prevent it from actually being used except in an
> outage. However, our route to 22943 appears to be using their backup
> link. (27270 4323 7018 22943 22943 22943 22943 22943 22943 22943 22943
> 22943 22943 22943) Which is strange, because we can reach their primary
> ISP without any such rigmarole.
It's not strange. AS path prepending like a typewriter monkey on crack
doesn't mean anything and certainly does not a "backup" link make.
Localpref can and will make it the best path anyway.
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