nanog mailing list archives
Re: Disaster recovery using as-prepend?
From: "Christopher L. Morrow" <christopher.morrow () verizonbusiness com>
Date: Fri, 17 Feb 2006 21:25:16 +0000 (GMT)
On Fri, 17 Feb 2006, Todd Vierling wrote:
On Thu, 16 Feb 2006, Warren Kumari wrote:If your primary is connected to ISP_A and the backup is connected to ISP_B, customers connected to ISP_B MAY still flow to your backup DC (ISP_B will probably set local preference on all customer routes - you should be able to override this behavior with communities but not all providers support this (or honor it 100% of the time!))And in addition to that, even multihomed customers of ISP_B may choose the prepended route for a number of different reasons; for instance, ISP_B might be a cheaper pipe for them, or there may be a smart-ish routing device or scheme in play that overrides normal BGP decision making.
I might be crazy, but couldn't you just prepend the route enough to effectively poison it at ingress to 'backup-isp' ? so they kept chosing the remote path and never really accept the route from local until the remote path is gone?
Current thread:
- Disaster recovery using as-prepend? Christopher J. Pilkington (Feb 16)
- Re: Disaster recovery using as-prepend? Andy Davidson (Feb 16)
- Re: Disaster recovery using as-prepend? Florian Weimer (Feb 16)
- Re: Disaster recovery using as-prepend? Ejay Hire (Feb 16)
- Re: Disaster recovery using as-prepend? Warren Kumari (Feb 16)
- Re: Disaster recovery using as-prepend? Todd Vierling (Feb 17)
- Re: Disaster recovery using as-prepend? Christopher L. Morrow (Feb 17)
- Re: Disaster recovery using as-prepend? Todd Vierling (Feb 17)
- Re: Disaster recovery using as-prepend? Todd Vierling (Feb 17)
- Re: Disaster recovery using as-prepend? Warren Kumari (Feb 17)
- Re: Disaster recovery using as-prepend? Christopher L. Morrow (Feb 17)
- Re: Disaster recovery using as-prepend? Todd Vierling (Feb 17)