From: Bit Gossip (bit.gossip@chello.nl)
Date: Sun Jun 24 2007 - 12:41:50 ART
maybe I should take a break....
I can not understand the BGP selection process for these 2 prefixes:
-for 28.119.16.0/24 the best next-hop is 204.12.1.254
-for 112.0.0.0 instead it is 54.1.3.254
Any idea why? The difference seems to be that the path with MED=0 is preferred
over the path with missing MED, but I have NOT configured 'bgp bestpath med
missing-as-worst' and so missing MED should be treated as MED=0
Rack1R6#show ip bgp 28.119.16.0/24
BGP routing table entry for 28.119.16.0/24, version 17
Paths: (2 available, best #2, table Default-IP-Routing-Table)
Flag: 0x820
Advertised to update-groups:
1 2
54
54.1.3.254 from 54.1.3.254 (212.18.3.1)
Origin IGP, localpref 100, valid, external
54
204.12.1.254 from 204.12.1.254 (31.3.0.1)
Origin IGP, metric 0, localpref 100, valid, external, best
Rack1R6#show ip bgp 112.0.0.0
BGP routing table entry for 112.0.0.0/8, version 4
Paths: (2 available, best #2, table Default-IP-Routing-Table)
Advertised to update-groups:
1 2
54 50 60
204.12.1.254 from 204.12.1.254 (31.3.0.1)
Origin IGP, localpref 100, valid, external
54 50 60
54.1.3.254 from 54.1.3.254 (212.18.3.1)
Origin IGP, metric 0, localpref 100, valid, external, best
This archive was generated by hypermail 2.1.4 : Sun Jul 01 2007 - 17:24:51 ART