nanog mailing list archives
Re: metric 0 vs 'no metric at all'
From: Danny McPherson <danny () tcb net>
Date: Tue, 3 Jan 2006 07:49:29 -0700
On Jan 3, 2006, at 1:03 AM, Daniel Roesen wrote:
So the spec is fuzzy about how "no MED vs. MED=0" should be treated, butvendors seem to largely agree to "no MED == MED 0". I know of nodeviation, except the old ERX bug which got fixed (ERX treated "no MED"as best, even better than MED=0 - contrary to documentation).
I recall some earlier implementations from "well known" vendors that had varying behavior for MED processing as well. Fortunately, the update to RFC 1771: http://www.ietf.org/internet-drafts/draft-ietf-idr-bgp4-26.txt is considerably more explicit about this behavior, as well as a slew of other previously-left-to-the-implementation items ironed out through a great deal of implementation and deployment experience. The "BGP Experience" and "BGP MED Considerations" Internet- drafts provide a good bit of additional insight into some of these behaviors. -danny
Current thread:
- metric 0 vs 'no metric at all' Alexander Koch (Jan 02)
- Re: metric 0 vs 'no metric at all' Daniel Roesen (Jan 03)
- Re: metric 0 vs 'no metric at all' Danny McPherson (Jan 03)
- Re: metric 0 vs 'no metric at all' Pierfrancesco Caci (Jan 03)
- Re: metric 0 vs 'no metric at all' Stephen J. Wilcox (Jan 03)
- Re: metric 0 vs 'no metric at all' Daniel Roesen (Jan 03)