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Re: EBGP peer is not advertising prefixes from other EBGP peer wh ile synchronization is enabled in Transit ASs posted 03/08/2006
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Chris,

Yes, both BGP and OSPF router-ids matches.

Mushtaq


On 3/8/06, Chris Lewis <chrlewiscsco@xxxxxxxxx> wrote:
>
> For the routes in question, does teh OSPF router ID match the BGP router
> ID?
>
> Chris
>
>
>  On 3/8/06, Mushtaq A. Khan <mak.ccie2b@xxxxxxxxx> wrote:
> >
> > Nick,
> >
> > Thanks for the tip but if you notice in my configuration I have already
> > redistributed BGP into IGP in their respective peer routers in AS100 to
> > put
> > these prefixes in the route table. When I checked the routes table all
> > three
> > routes shows there as well but this is still not working.
> >
> > Mushtaq
> >
> >
> > On 3/8/06, Popgeorgiev Nikolay < nikolay.popgeorgiev@xxxxxxxxxxx> wrote:
> > >
> > > Dear Mushtaq,
> > >
> > >
> > > I didn't go really through all your post but I can tell you how I did
> > this
> > > thing and what problems I faced in a similar task:
> > >
> > > I used RR in AS 100, R1 as a route reflector and R2 as its client.
> > > Because the requirement says do't disable synchronization, in order
> > for R1
> > > for example to put network 20.20.20.20 into its routing table, it has
> > to
> > > have this route known already via IGP or static or connected.
> > > So my solution is to redistribute BGP into IGP on router R2. This is
> > not a
> > > very clever thing to do if you have many routes coming from BGP but in
> > this
> > > case helps :)
> > >
> > >
> > > Try it and if I have missed something in your explanations sorry about
> > > that
> > >
> > > Best,
> > > Nick
> > >
> > >
> > >
> > >
> > >
> > > -----Original Message-----
> > > From: Mushtaq A. Khan [mailto:mak.ccie2b@xxxxxxxxx]
> > > Sent: Wednesday, March 08, 2006 7:59 AM
> > > To: ccielab@xxxxxxxxxxxxxx
> > > Subject: EBGP peer is not advertising prefixes from other EBGP peer
> > while
> > > synchronization is enabled in Transit ASs
> > >
> > > Hi Team,
> > >
> > > I have a scenario as shown below.
> > >
> > >     SW2(AS200) ----(RIP)-----R2(AS100)
> > >                                                       \
> > >                                                      (OSPF)
> > >                                                        \
> > >                                                         R1(AS100)
> > > -----(OSPF)----R6(AS600)
> > >                                                         /
> > >                                                       (OSPF)
> > >                                                        /
> > >      R5(AS600)-----EIGRP-----R3(AS100)
> > >
> > > The task is to advertise the following prefixes in BGP ONLY within
> > their
> > > respective ASs and these should be exchanged between all AS's.
> > >
> > >     20.20.20.20(SW2)
> > >      5.5.5.5 (R5)
> > >      6.6.6.6 (R6)
> > >
> > > AS100 should provide transit path between the above prefixes and MUST
> > not
> > > disable synchronization and use minimal number of BGP speakers.
> > >
> > > One solution to above requirement is to use BGP confederation within
> > > AS100.
> > > I tried to solve this using route reflector and facing difficulty: I
> > > noticed
> > > R6 is able to see all 3 prefixes in its BGP table. However, R5 and SW2
> > > can't
> > > see each other prefixes. I tried different options but with no luck.
> > > Anyone
> > > has any clue to resolve this issue here.
> > >
> > > All relevent configuration are given below:
> > >
> > > R2#sh run | beg router bgp
> > > router bgp 100
> > > synchronization
> > > bgp log-neighbor-changes
> > > neighbor 172.16.20.10 remote-as 200
> > > neighbor 172.16.101.1 remote-as 100
> > > neighbor 172.16.101.1 update-source Loopback102
> > > no auto-summary
> > > !
> > > R2#sh run | beg router ospf|route-map
> > > router ospf 1
> > > log-adjacency-changes
> > > redistribute rip subnets
> > > redistribute bgp 100 subnets route-map BGPtoOSPF
> > > network 172.16.102.1 0.0.0.0 area 20
> > > network 172.16.123.2 0.0.0.0 area 0
> > > !
> > > ip prefix-list BGP-Route seq 5 permit 20.20.20.0/24
> > > !
> > > route-map BGPtoOSPF permit 10
> > > match ip address prefix-list BGP-Route
> > >
> > > R2#sh ip bgp | beg Network
> > >   Network          Next Hop            Metric LocPrf Weight Path
> > > * i5.5.5.0/24       172.16.35.5              0    100      0 500 i
> > > r>i6.6.6.0/24       172.16.16.6              0    100      0 600 i
> > > *> 20.20.20.0/24    172.16.20.10             0             0 200 i
> > >
> > > sw2#sh ip bgp | beg Network
> > >   Network          Next Hop            Metric LocPrf Weight Path
> > > *> 6.6.6.0/24       172.16.20.2                            0 100 600 i
> > > *> 20.20.20.0/24     0.0.0.0                  0         32768 i
> > >
> > > R1#sh run | beg router ospf|route-map
> > > router ospf 1
> > > router-id 172.16.101.1
> > > redistribute bgp 100 subnets route-map BGPtoOSPF
> > > !
> > > router bgp 100
> > > synchronization
> > > bgp log-neighbor-changes
> > > neighbor AS100 peer-group
> > > neighbor AS100 remote-as 100
> > > neighbor AS100 update-source Loopback101
> > > neighbor AS100 route-reflector-client
> > > neighbor 172.16.16.6 remote-as 600
> > > neighbor 172.16.102.1 peer-group AS100
> > > neighbor 172.16.103.1 peer-group AS100
> > > no auto-summary
> > > !
> > > !
> > > ip prefix-list BGP-Routes seq 5 permit 6.6.6.0/24
> > > !
> > > route-map BGPtoOSPF permit 10
> > > match ip address prefix-list BGP-Routes
> > > !
> > >
> > > R1#sh ip bgp | beg Network
> > >   Network          Next Hop            Metric LocPrf Weight Path
> > > r>i5.5.5.0/24       172.16.35.5              0    100      0 500 i
> > > *> 6.6.6.0/24       172.16.16.6              0             0 600 i
> > > r>i20.20.20.0/24    172.16.20.10              0    100      0 200 i
> > >
> > > R6#sh ip bgp | beg Network
> > >   Network          Next Hop            Metric LocPrf Weight Path
> > > *> 5.5.5.0/24       172.16.16.1                            0 100 500 i
> > > *> 6.6.6.0/24       0.0.0.0                  0         32768 i
> > > *> 20.20.20.0/24    172.16.16.1                            0 100 200 i
> > >
> > > R3#sh run | beg router ospf|route-map
> > > router ospf 1
> > > log-adjacency-changes
> > > redistribute bgp 100 subnets route-map BGPtoOSPF
> > >
> > >
> > > router bgp 100
> > > synchronization
> > > bgp log-neighbor-changes
> > > neighbor 172.16.35.5 remote-as 500
> > > neighbor 172.16.101.1 remote-as 100
> > > neighbor 172.16.101.1 update-source Loopback103
> > > no auto-summary
> > > !
> > >
> > > !
> > > ip prefix-list BGP-Routes seq 5 permit 5.5.5.0/24
> > > !
> > > route-map BGPtoOSPF permit 10
> > > match ip address prefix-list BGP-Routes
> > >
> > > R3#sh ip bgp | beg Network
> > >   Network          Next Hop            Metric LocPrf Weight Path
> > > *> 5.5.5.0/24       172.16.35.5              0             0 500 i
> > > r>i6.6.6.0/24       172.16.16.6              0    100      0 600 i
> > > * i20.20.20.0/24    172.16.20.10             0    100      0 200 i
> > > R3#
> > > R5#sh ip bgp | beg Network
> > >   Network          Next Hop            Metric LocPrf Weight Path
> > > *> 5.5.5.0/24       0.0.0.0                  0         32768 i
> > > *> 6.6.6.0/24       172.16.35.3                            0 100 600 i
> > >
> > > TIA,
> > > Mushtaq
> > >
> > >
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