RE: NMC Sample LAB - BGP Sync and OSPF

From: Pun, Alec CL (Alec.CL.Pun@pccw.com)
Date: Sun Nov 30 2003 - 22:32:36 GMT-3

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If synchronization is enabled and the underlying IGP is OSPF, make sure the
router ID for prefix that appear in OSPF and BGP table must be the SAME.
This is an extra requirement for OSPF only.

regards,
alec

-----Original Message-----
From: Jonathan V Hays [mailto:jhays@jtan.com]
Sent: Sunday, November 30, 2003 9:57 PM
To: 'Martin D. Fierbaugh'; ccielab@groupstudy.com
Subject: RE: NMC Sample LAB - BGP Sync and OSPF

Going back to my notes, I see I have noted that I think the NMC solution
is incorrect for this particular problem.

From page 41 of the Sample Scenario PDF:

"Issue: Use the default synchronization method on R2 and R3. Solution:
Redistribute EBGP learned updates on router R2 into OSPF."

But the result of redistributing EBGP into OSPF on R2 is that OSPF says
that 192.168.x.x routes originate from R2 while BGP says the routes
originate from R1. Result: not synchronized.

I found that when I redistributed BGP into OSPF on R1 the problem was
solved.

HTH,

Jonathan

-----Original Message-----
From: nobody@groupstudy.com [mailto:nobody@groupstudy.com] On Behalf Of
Martin D. Fierbaugh
Sent: Sunday, November 30, 2003 8:11 AM
To: ccielab@groupstudy.com
Subject: NMC Sample LAB - BGP Sync and OSPF

After reading many posts in the archives, I came across this scenario.

In order to satisfy a requirement in this lab, you need to leave
synchronization turned on in an iBGP environment and pass the
announcement to a route reflector client. OSPF has the IGP route, route
is in the routing table, yet BGP seems to think the route is not
synchronized.

Based upon a few posts, I see that this is either intentionally or
unintentionally broken in IOS (proof below).

My questions are is it, in fact, broken? If so, why is it even on
this lab?

Anyone else try this sample lab and run into this?

NMC practice lab, section 8

Thanks,
________________________________
Martin D. Fierbaugh, CCNP
Manager IP Routing
NTELOS Advanced Data Engineering
(w) 304.353.8916
(m) 304.415.0427

sh ip route...
C 172.16.123.0/24 is directly connected, Serial0/0
O E2 172.16.77.0/24 [110/20] via 172.16.123.1, 00:40:27, Serial0/0
O E2 192.168.102.0/24 [110/1] via 172.16.123.1, 00:40:27, Serial0/0
O E2 192.168.103.0/24 [110/1] via 172.16.123.1, 00:40:27, Serial0/0
O E2 192.168.100.0/24 [110/1] via 172.16.123.1, 00:40:27, Serial0/0
O E2 192.168.101.0/24 [110/1] via 172.16.123.1, 00:40:27, Serial0/0
O*E2 0.0.0.0/0 [110/1] via 172.16.123.2, 00:40:27, Serial0/0

R3#sh ip bgp 192.168.100.0
BGP routing table entry for 192.168.100.0/24, version 0
Paths: (1 available, no best path)
  Not advertised to any peer
  100 700
    172.16.123.1 from 172.16.2.1 (172.16.20.5)
      Origin incomplete, localpref 100, valid, internal, not
synchronized
R3#

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Next message: Brian Dennis: "RE: OSPF Question..."
Previous message: Brian McGahan: "RE: Why Disabling BPG soft-reconfig did not reclaim Memory?"
Maybe in reply to: Martin D. Fierbaugh: "NMC Sample LAB - BGP Sync and OSPF"
Next in thread: Jonathan V Hays: "RE: NMC Sample LAB - BGP Sync and OSPF"
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