From: OhioHondo (ohiohondo@columbus.rr.com)
Date: Fri May 09 2003 - 10:33:07 GMT-3
If the next-hop were not reachable there would be an indication in the "sho
ip bgp x.x.x.x" command. It looks like your next hop is reachable.
Go to the origin of the route and do a "sho ip bgp x.x.x.x" and find out
which route BGP has selected as Best Route. Make sure the OSPF and BGP
router ID's on THAT ROUTER are the same.
Now the BGP and OSPF processes in your network propagate their respective
best routes to your problem router. If they are not both from the same
"router of origin" (that has an identical BGP and OSPF router-id) -- then
you are not synchronized.
-----Original Message-----
From: nobody@groupstudy.com [mailto:nobody@groupstudy.com]On Behalf Of
Alexander Arsenyev (ETL)
Sent: Friday, May 09, 2003 7:26 AM
To: 'Pierrre-Alex GUANEL'; ccielab@groupstudy.com
Subject: RE: BGP route not synchronized -- WEIRED! Check R7 router-ids
Are R7 BGP router-id and R7 OSPF router-id the same? Check RFC1403 section
3.
Please post R7 OSPF config here.
Cheers
Alex
-----Original Message-----
From: Pierrre-Alex GUANEL [mailto:pierreg@experttraining.net]
Sent: 09 May 2003 09:39
To: Brian Dennis; 'Pierrre-Alex GUANEL'; ccielab@groupstudy.com;
BPOU@ch.ibm.com
Cc: 'Cisco'; Xy Le
Subject: RE: BGP route not synchronized -- WEIRED!
Thanks for your replies.
1) There are no default routes in this network
The next hop (a loopback with a 32 bit mask) was learned via OSPF and is
reachable via OSPF.
The 188.1.2.0/24 route was learned by redistributing bgp into OSPF (so
should be synchronized!!!)
There is only one bgp route in the routing table of R1
2) I have posted my partial configs below for R1. Maybe something obvious I
missed!
Exhibit 5 ---> BGP Configuration
Exhibit 6 ---> OSPF Configuration
Exhibit 7----> Routing table
Exhibit 8----> BGP Table
---------------------- exhibit 5 ---------------------------------------
R1#show run | b bgp
router bgp 65531
bgp router-id 1.1.1.1
bgp cluster-id 1
bgp log-neighbor-changes
neighbor Remote peer-group
neighbor Remote remote-as 65531
neighbor Remote update-source Loopback100
neighbor Remote route-reflector-client
neighbor Remote soft-reconfiguration inbound
neighbor 10.0.50.1 remote-as 65531 ! R5
neighbor 10.0.70.1 remote-as 65531 ! R7
neighbor 10.0.50.1 update-source Loopback100
neighbor 10.0.70.1 update-source Loopback100
neighbor 10.3.100.1 peer-group Remote ! R3
neighbor 10.4.100.1 peer-group Remote ! R4
------------------------exhibit 6 ----------------------------------------
R1#show run | b ospf
router ospf 100
router-id 1.1.1.1
log-adjacency-changes
network 10.0.0.0 0.0.0.255 area 0
network 10.1.0.0 0.0.0.3 area 4
network 10.2.0.0 0.0.0.3 area 3
network 10.100.0.1 0.0.0.0 area 0
------------------------exhibit 7-----------------------------------------
R1#show ip route ospf
188.1.0.0/24 is subnetted, 1 subnets
O E1 188.1.2.0 [110/106] via 10.0.0.7, 03:47:08, TokenRing0
10.0.0.0/8 is variably subnetted, 17 subnets, 5 masks
O 10.1.0.3/32 [110/64] via 10.1.0.3, 05:10:28, Serial0.4
O E1 10.3.0.0/16 [110/164] via 10.2.0.3, 03:47:08, Serial0.3
O 10.1.0.2/32 [110/128] via 10.1.0.3, 05:10:28, Serial0.4
O 10.2.0.2/32 [110/128] via 10.2.0.3, 05:06:59, Serial0.3
O 10.2.0.3/32 [110/64] via 10.2.0.3, 05:06:59, Serial0.3
O E1 10.6.0.0/30 [110/106] via 10.0.0.5, 03:47:08, TokenRing0
O E1 10.4.0.0/16 [110/164] via 10.1.0.3, 03:47:08, Serial0.4
O E1 10.5.0.0/16 [110/106] via 10.0.0.5, 03:47:08, TokenRing0
O 10.0.50.1/32 [110/7] via 10.0.0.5, 03:47:18, TokenRing0
O 10.0.70.1/32 [110/7] via 10.0.0.7, 03:47:18, TokenRing0
O 10.4.100.1/32 [110/65] via 10.1.0.3, 05:10:28, Serial0.4
O 10.3.100.1/32 [110/65] via 10.2.0.3, 05:06:59, Serial0.3
O 10.200.0.1/32 [110/7] via 10.0.0.2, 03:47:18, TokenRing0
------------------------exhibit
8 ------------------------------------------------
R1#show ip bgp
BGP table version is 1, local router ID is 1.1.1.1
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
* i188.1.2.0/24 10.0.70.1 0 100 0 1 i
R1#
R1#show ip bgp
BGP table version is 1, local router ID is 1.1.1.1
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
* i188.1.2.0/24 10.0.70.1 0 100 0 1 i
R1#show ip bgp 188.1.2.0
BGP routing table entry for 188.1.2.0/24, version 0
Paths: (1 available, no best path)
Not advertised to any peer
1
10.0.70.1 (metric 7) from 10.0.70.1 (10.0.70.1)
Origin IGP, metric 0, localpref 100, valid, internal, not synchronized
============================================================================
==
Pierre-Alex
-----Original Message-----
From: Brian Dennis [mailto:brian@labforge.com]
Sent: Friday, May 09, 2003 7:22 AM
To: 'Pierrre-Alex GUANEL'; ccielab@groupstudy.com
Cc: 'Cisco'
Subject: RE: BGP route not synchronized -- WEIRED!
Just because the next hop is pingable it does not mean it's a valid next
hop. Next hop addresses that are reachable only via a default route
aren't valid. Also next hop addresses that are reachable only via
another BGP route are also not valid.
Brian Dennis, CCIE #2210 (R&S/ISP-Dial/Security)
Director of CCIE Training and Development - IPexpert, Inc.
Mailto: brian@ipexpert.net
Toll Free: 866.225.8064
Outside U.S. & Canada: 312.321.6924
-----Original Message-----
From: nobody@groupstudy.com [mailto:nobody@groupstudy.com] On Behalf Of
Pierrre-Alex GUANEL
Sent: Thursday, May 08, 2003 10:24 PM
To: ccielab@groupstudy.com
Cc: Cisco
Subject: BGP route not synchronized -- WEIRED!
I have a problem with a router not advertising internal bgp routes to
its
peers (exhibit1)
The route (188.1.2.0/24) is synchronized (exhibit 2) and the next hop is
reacheable (exhibit 3) but the router still does not accept the route as
synchronized (exhibit 4)
The router is running IOS c2500-js-l.121-5.T.bin. I am puzzled. Any
ideas ?
R1#show ip bgp
BGP table version is 1, local router ID is 1.1.1.1
Status codes: s suppressed, d damped, h history, * valid, > best, i -
internal
Origin codes: i - IGP, e - EGP, ? - incomplete
-------------------- exhibit 1
Network Next Hop Metric LocPrf Weight Path
* i188.1.2.0/24 10.0.70.1 0 100 0 1 i
-------------------- exhibit 2
R1#show ip route ospf | i 188.1.2.0
O E1 188.1.2.0 [110/106] via 10.0.0.7, 00:21:23, TokenRing0
-------------------- exhibit 3
R1#ping 10.0.70.1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 10.0.70.1, timeout is 2 seconds:
!!!!!
--------------------------- exhibit 4
Success rate is 100 percent (5/5), round-trip min/avg/max = 8/8/8 ms
R1#show ip bgp 188.1.2.0
BGP routing table entry for 188.1.2.0/24, version 0
Paths: (1 available, no best path)
Not advertised to any peer
1
10.0.70.1 (metric 7) from 10.0.70.1 (10.0.70.1)
Origin IGP, metric 0, localpref 100, valid, internal, not
synchronized
Thanks,
Pierre-Alex
This archive was generated by hypermail 2.1.4 : Mon Jun 02 2003 - 15:13:39 GMT-3