From: Peter Dostal (pdostal@xxxxxxx)
Date: Mon Apr 08 2002 - 04:46:24 GMT-3
Chang,
You are absolutely right! Sometimes I just don't consider the most obvious
reason. Thanks for this excellent input as well as thanks to everybody who
tried to help with this problem.
Peter
-----Original Message-----
From: ying chang [mailto:ying_c@hotmail.com]
Sent: Saturday, April 06, 2002 8:56 PM
To: Upp_and_Upp@hotmail.com; ccielab@groupstudy.com
Subject: Re: BGP MED - again (Solved with clean copy)
Hi all,
Below is the config and output. The problem was originated from Peter's
earlier post. Noticed on R2 192.168.1.0 from R3 is suppressed as shown in
the debug.
Thanks,
Chang
R1: (AS1, connect to R2 and R3 in AS236 via ebgp, will hint AS236 to prefer
R1-R2 route)
!
router bgp 1
bgp log-neighbor-changes
network 192.168.1.0 <<<<-- network to be advertised
neighbor 10.1.1.2 remote-as 236
neighbor 10.1.1.2 soft-reconfiguration inbound
neighbor 10.1.1.2 route-map set-med1 out
neighbor 10.1.1.3 remote-as 236
neighbor 10.1.1.3 soft-reconfiguration inbound
neighbor 10.1.1.3 route-map set-med2 out
!
!
route-map set-med2 permit 10
set metric 30
!
route-map set-med1 permit 10
set metric 20 <<<<-- lower MED to make R1-R2 route more attractive
!
====================
r1#sib
BGP table version is 4, local router ID is 192.168.1.1
Status codes: s suppressed, d damped, h history, * valid, > best, i -
internal
Origin codes: i - IGP, e - EGP, ? - incomplete
Network Next Hop Metric LocPrf Weight Path
* 26.1.1.0/24 10.1.1.3 0 236 i
*> 10.1.1.2 0 236 i
* 36.1.1.0/24 10.1.1.3 0 0 236 i
*> 10.1.1.2 0 236 i
*> 192.168.1.0 0.0.0.0 0 32768 i
r1#
-----------------------------
R2: (AS236, R2-R1 is the preferred route to AS1)
r2#sb router
router ospf 100
router-id 26.1.1.2
log-adjacency-changes
passive-interface default
no passive-interface Ethernet1
no passive-interface Serial0
network 0.0.0.0 255.255.255.255 area 0
!
router bgp 236
no synchronization
bgp router-id 26.1.1.2
bgp log-neighbor-changes
neighbor 10.1.1.1 remote-as 1
neighbor 10.1.1.1 soft-reconfiguration inbound
neighbor 26.1.1.6 remote-as 236
neighbor 26.1.1.6 next-hop-self
neighbor 36.1.1.3 remote-as 236
neighbor 36.1.1.3 next-hop-self
neighbor 36.1.1.3 soft-reconfiguration inbound
!
r2#sib
BGP table version is 7, local router ID is 26.1.1.2
Status codes: s suppressed, d damped, h history, * valid, > best, i -
internal
Origin codes: i - IGP, e - EGP, ? - incomplete
Network Next Hop Metric LocPrf Weight Path
*>i26.1.1.0/24 26.1.1.6 0 100 0 i
* i36.1.1.0/24 36.1.1.3 0 100 0 i
*>i 26.1.1.6 0 100 0 i
*> 192.168.1.0 10.1.1.1 20 0 1 i
r2#
...
11:18:03: BGP(0): 26.1.1.6 computing updates, afi 0, neighbor version 0,
table v
ersion 5, starting at 0.0.0.0
11:18:03: BGP(0): 26.1.1.6 send UPDATE (format) 192.168.1.0/24, next
26.1.1.2, m
etric 20, path 1
11:18:03: BGP(0): 26.1.1.6 1 updates enqueued (average=59, maximum=59)
11:18:03: BGP(0): 26.1.1.6 update run completed, afi 0, ran for 16ms,
neighbor v
ersion 0, start version 5, throttled to 5
11:18:03: BGP: 26.1.1.6 initial update completed#
r2#
11:18:07: BGP(0): 36.1.1.3 computing updates, afi 0, neighbor version 4,
table v
ersion 5, starting at 0.0.0.0
11:18:07: BGP(0): 36.1.1.3 send UPDATE (format) 192.168.1.0/24, next
26.1.1.2, m
etric 20, path 1
11:18:07: BGP(0): 36.1.1.3 1 updates enqueued (average=59, maximum=59)
11:18:07: BGP(0): 36.1.1.3 update run completed, afi 0, ran for 12ms,
neighbor v
ersion 4, start version 5, throttled to 5
11:18:08: BGP(0): 36.1.1.3 rcv UPDATE about 192.168.1.0/24 -- withdrawn
------------------------------------------
R3: (AS236, backup border router to AS1)
r3#sb router
router ospf 100
router-id 36.1.1.3
log-adjacency-changes
passive-interface default
no passive-interface Ethernet0
no passive-interface Serial0
network 0.0.0.0 255.255.255.255 area 0
!
router bgp 236
no synchronization
bgp log-neighbor-changes
network 36.1.1.0 mask 255.255.255.0
neighbor 10.1.1.1 remote-as 1
neighbor 10.1.1.1 soft-reconfiguration inbound
neighbor 26.1.1.2 remote-as 236
neighbor 26.1.1.2 next-hop-self
neighbor 26.1.1.2 soft-reconfiguration inbound
neighbor 36.1.1.6 remote-as 236
neighbor 36.1.1.6 next-hop-self
neighbor 36.1.1.6 soft-reconfiguration inbound
!
r3#sib
BGP table version is 8, local router ID is 36.1.1.3
Status codes: s suppressed, d damped, h history, * valid, > best, i -
internal
Origin codes: i - IGP, e - EGP, ? - incomplete
Network Next Hop Metric LocPrf Weight Path
*>i26.1.1.0/24 36.1.1.6 0 100 0 i
*> 36.1.1.0/24 0.0.0.0 0 32768 i
* i 36.1.1.6 0 100 0 i
*>i192.168.1.0 26.1.1.2 20 100 0 1 i
* 10.1.1.1 30 0 1 i
r3#
----------------------------------------
R6: (AS236, internal router, have to go through R2 or R3 to reach AS1)
r6#sb router
router ospf 100
router-id 36.1.1.6
log-adjacency-changes
passive-interface default
no passive-interface Ethernet0
no passive-interface Ethernet1
network 0.0.0.0 255.255.255.255 area 0
!
router bgp 236
no synchronization
bgp router-id 36.1.1.6
bgp log-neighbor-changes
network 26.1.1.0 mask 255.255.255.0
network 36.1.1.0 mask 255.255.255.0
neighbor 26.1.1.2 remote-as 236
neighbor 26.1.1.2 soft-reconfiguration inbound
neighbor 36.1.1.3 remote-as 236
neighbor 36.1.1.3 soft-reconfiguration inbound
!
r6#sib
BGP table version is 7, local router ID is 36.1.1.6
Status codes: s suppressed, d damped, h history, * valid, > best, i -
internal
Origin codes: i - IGP, e - EGP, ? - incomplete
Network Next Hop Metric LocPrf Weight Path
*> 26.1.1.0/24 0.0.0.0 0 32768 i
* i36.1.1.0/24 36.1.1.3 0 100 0 i
*> 0.0.0.0 0 32768 i
*>i192.168.1.0 26.1.1.2 20 100 0 1 i
r6#
This archive was generated by hypermail 2.1.4 : Thu Jun 13 2002 - 10:57:59 GMT-3