From: Felice Russell (felicear@sbcglobal.net)
Date: Wed Jul 07 2004 - 14:27:19 GMT-3
James,
It sounds like there may be an underlying protocol issue. Using
Next-hop-self can sometimes mask the problem. I have also found documents
on CCO (well, at least one document) which advised against ever using
next-hop-self with route-reflectors. I don't know if that should be taken as
gospel but you can decide that for yourself. As long as bgp knows it
requires a few hops (ie ebgp-multihop) there is not reason you should not be
able to ping as long as the connecting networks are somehow reachable.
r2--> bgp & rrc to r7----r4(no bgp)------<--r7 bgp
I am sure this is as clear as mud...but to elaborate:
show ip bgp on r2
BGP table version is 22, local router ID is 200.200.22.22 Status codes: s
suppressed, d damped, h history, * valid, > best, i -
internal,
r RIB-failure, S Stale
Origin codes: i - IGP, e - EGP, ? - incomplete
Network Next Hop Metric LocPrf Weight Path
*> 122.122.122.0/24 0.0.0.0 0 32768 i
*>i177.177.177.0/24 150.50.77.77 0 100 0 I
The network 150.50.77.77 must be reachable. This is assuming that the
network leading to R7 is the 150.50.77.77....which actually looks more like
a loopback. Can you ping the loopback? If not, I would correct that first
and then try to ping the bgp route.
Best Regards,
Felice
-----Original Message-----
From: nobody@groupstudy.com [mailto:nobody@groupstudy.com] On Behalf Of
Peter Ding
Sent: Monday, July 05, 2004 8:43 AM
To: 'Tom Martin'; ccielab@groupstudy.com
Cc: 'James Yeo'
Subject: RE: I-BGP
Using policy routing on r4 can also achieve the objective...
PD
-----Original Message-----
From: nobody@groupstudy.com [mailto:nobody@groupstudy.com] On Behalf Of Tom
Martin
Sent: Sunday, July 04, 2004 3:43 PM
To: ccielab@groupstudy.com
Cc: James Yeo
Subject: RE: I-BGP
James,
That leaves options 1 and 3 which should work fine. Here's sample output
from my lab using a GRE tunnel, topology: R7 <--> R4 <--> R8, IGP is OSPF.
The configuration should be apparent from the output below but let me know
if you have questions on the config.
r7#show ip route
... header lines removed ...
C 192.168.47.0/24 is directly connected, Serial0
C 192.168.78.0/24 is directly connected, Tunnel0
C 7.0.0.0/8 is directly connected, Loopback0
B 8.0.0.0/8 [200/0] via 192.168.78.8, 00:02:06
O 192.168.48.0/24 [110/128] via 192.168.47.4, 00:06:20, Serial0
r4# show ip route
... header lines removed ...
C 192.168.47.0/24 is directly connected, Serial0/1
C 192.168.48.0/24 is directly connected, Serial0/0
r8# show ip route
... header lines removed ...
O 192.168.47.0/24 [110/128] via 192.168.48.4, 00:07:50, Serial0/0
C 192.168.78.0/24 is directly connected, Tunnel0
B 7.0.0.0/8 [200/0] via 192.168.78.7, 00:03:20
C 8.0.0.0/8 is directly connected, Loopback0
C 192.168.48.0/24 is directly connected, Serial0/0
r7#ping 8.8.8.8
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 8.8.8.8, timeout is 2 seconds: !!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 36/36/36 ms
r4#ping 8.8.8.8
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 8.8.8.8, timeout is 2 seconds: .....
Success rate is 0 percent (0/5)
r4#ping 7.7.7.7
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 7.7.7.7, timeout is 2 seconds: .....
Success rate is 0 percent (0/5)
r8#ping 7.7.7.7
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 7.7.7.7, timeout is 2 seconds: !!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 36/36/36 ms
-- Tom
-----Original Message-----
From: nobody@groupstudy.com [mailto:nobody@groupstudy.com]On Behalf Of James
Yeo
Sent: Sunday, July 04, 2004 5:12 PM
To: Tom Martin; ccielab@groupstudy.com
Subject: RE: I-BGP
Hi Tom,
Basically lab sets up i-bgp between r2 and r7 using "rrc" however that works
fine and routes show up etc. Problem is there is r4 in the middle not
running bgp as a process therefore when you try and ping the i-bgp networks
it fails because "piggy in the middle" is clueless with regards to those
routes. You are not told to redistribute or configure bgp on r4.
I was wondering if it possible on Gods' green earth to be able to ping...
I think not
What do you think?
Kind regards
James
-----Original Message-----
From: nobody@groupstudy.com [mailto:nobody@groupstudy.com] On Behalf Of Tom
Martin
Sent: Friday, July 02, 2004 10:39 PM
To: ccielab@groupstudy.com
Cc: James R. Yeo
Subject: RE: I-BGP
James,
It is a little unclear exactly what you are trying to accomplish and what
lab requirements/restrictions there are. Here are some suggestions:
1. MPLS
2. Run BGP on R4 (peer to R7 as RR client)
3. Tunnel BGP and transit traffic through R4
4. Redistribute BGP into the IGP
-- Tom
-----Original Message-----
From: nobody@groupstudy.com [mailto:nobody@groupstudy.com] On Behalf Of
James R. Yeo
Sent: Friday, July 02, 2004 4:17 PM
To: ccielab@groupstudy.com
Subject: I-BGP
Hi group,
If you have i-bgp running with route-reflectors and they are not directly
connected e.g.
r2--> bgp & rrc to r7----r4(no bgp)------<--r7 bgp
Can you ping!! Routes show up in table but cannot ping as it dies @ r4 as
r4 has no idea about the bgp networks.
Route table on r2:
177.177.0.0/24 is subnetted, 1 subnets
B 177.177.177.0 [200/0] via 150.50.77.77, 00:28:31
show ip bgp on r2
BGP table version is 22, local router ID is 200.200.22.22 Status codes: s
suppressed, d damped, h history, * valid, > best, i -
internal,
r RIB-failure, S Stale
Origin codes: i - IGP, e - EGP, ? - incomplete
Network Next Hop Metric LocPrf Weight Path
*> 122.122.122.0/24 0.0.0.0 0 32768 i
*>i177.177.177.0/24 150.50.77.77 0 100 0 i
Any comments!?
This archive was generated by hypermail 2.1.4 : Sun Aug 01 2004 - 10:11:48 GMT-3