nanog mailing list archives
RE: AS PATH limits
From: "Jakob Heitz (jheitz)" <jheitz () cisco com>
Date: Thu, 21 Sep 2017 18:51:04 +0000
The consequence of keeping a route with a long AS_PATH is that it uses a little more memory. Also, if you send it on, you will add one ASN and may exceed the maximum BGP message size and not be able to send it. Even that is no reason to drop the incoming route. The consequence of dropping the route is that someone loses connectivity because you dropped it. The need for limiting AS_PATH length stemmed from this incident: https://dyn.com/blog/the-flap-heard-around-the-world/ This bug has long been fixed, so it should not happen again. However, if you want to be extra cautious, because unpatched routers may still be out there, then 200 should not drop any normal route. Just keep an eye on what you are dropping Thanks, Jakob Date: Tue, 19 Sep 2017 13:33:03 +0000 From: craig washington <craigwashington01 () hotmail com> To: "nanog () nanog org" <nanog () nanog org> Subject: AS PATH limits Message-ID: <SN1PR0701MB206268455259CC64FC0D8ED7A8600 () SN1PR0701MB2062 namprd07 prod outlook com> Content-Type: text/plain; charset="iso-8859-1" Hello world. I was wondering and forgive me if this discussions has already taken place. How many AS PATHS are too many? Meaning how do we determine how many to filter on transit links or public peering links? Thanks in advance
Current thread:
- AS PATH limits craig washington (Sep 20)
- Re: AS PATH limits valdis . kletnieks (Sep 20)
- Re: AS PATH limits Tim Evens (Sep 20)
- Re: AS PATH limits Randy Bush (Sep 20)
- Re: AS PATH limits jim deleskie (Sep 20)
- Re: AS PATH limits Randy Bush (Sep 20)
- Re: AS PATH limits Tom Beecher (Sep 20)
- Re: AS PATH limits craig washington (Sep 22)
- <Possible follow-ups>
- RE: AS PATH limits Jakob Heitz (jheitz) (Sep 21)
- Re: AS PATH limits Ken Chase (Sep 30)
- Re: AS PATH limits sthaug (Sep 30)
- Re: AS PATH limits jim deleskie (Sep 30)
- Message not available
- Re: AS PATH limits Ken Chase (Sep 30)
- Re: AS PATH limits Christopher Morrow (Sep 30)
- Re: AS PATH limits Ken Chase (Sep 30)
- Re: AS PATH limits William Herrin (Sep 30)
- Re: AS PATH limits Hank Nussbacher (Sep 30)
- Re: AS PATH limits Mikael Abrahamsson (Sep 30)
- Re: AS PATH limits sthaug (Sep 30)