nanog mailing list archives
Re: Multi site BGP Routing design
From: Saqib Ilyas <msaqib () gmail com>
Date: Sat, 6 Jun 2009 17:21:29 +0500
For a given interconnection between the upstream ISPs for the two site, once the direct link goes down, the time required for site A to learn the new route to site B and vice versa would be different with the different proposed solutions, right? Thanks and best regards On Sat, Jun 6, 2009 at 12:40 PM, Ivan Pepelnjak <ip () ioshints info> wrote:
To rephrase the OP's question, would it be BCP to acquire a second ASN, and without further de-aggregating, continue advertising each site's IP space to the DFZ, but from dissimilar ASs as opposed to the same one?This would definitely be the best approach. You're not introducing new IP prefixes and you're not extending AS paths, so the net effect on the global BGP routing is zero (OK, you might have to use the 4 byte AS number :). Just make sure that both ISPs you connect to allow you to advertise "transit" prefixes. If site A public link goes down, but the private link is up, site B will advertise its own address space plus site A's address space with an extra AS number in the AS path (and the upstream ISP might filter that). Ivan http://www.ioshints.info/about http://blog.ioshints.info/
-- Muhammad Saqib Ilyas PhD Student, Computer Science and Engineering Lahore University of Management Sciences
Current thread:
- Multi site BGP Routing design Justin Krejci (Jun 05)
- Re: Multi site BGP Routing design Steve Bertrand (Jun 05)
- Re: Multi site BGP Routing design Chris Adams (Jun 05)
- RE: Multi site BGP Routing design John.Herbert (Jun 05)
- Re: Multi site BGP Routing design Steve Bertrand (Jun 05)
- RE: Multi site BGP Routing design John.Herbert (Jun 05)
- Re: Multi site BGP Routing design Chris Adams (Jun 05)
- Re: Multi site BGP Routing design Steve Bertrand (Jun 05)
- Re: Multi site BGP Routing design Michael K. Smith (Jun 05)
- Re: Multi site BGP Routing design Steve Bertrand (Jun 05)
- RE: Multi site BGP Routing design Ivan Pepelnjak (Jun 06)
- Re: Multi site BGP Routing design Saqib Ilyas (Jun 06)
- Re: Multi site BGP Routing design Adam Greene (Jun 06)
- RE: Multi site BGP Routing design Justin Krejci (Jun 08)
- RE: Multi site BGP Routing design Ivan Pepelnjak (Jun 09)
- Re: Multi site BGP Routing design Steve Bertrand (Jun 05)
- RE: Multi site BGP Routing design John.Herbert (Jun 05)
- Re: Multi site BGP Routing design Chuck Anderson (Jun 05)
- Re: Multi site BGP Routing design Steve Bertrand (Jun 05)
- Re: Multi site BGP Routing design Randy Bush (Jun 05)
- Re: Multi site BGP Routing design Steve Bertrand (Jun 05)