Hi,
We've setup BGP as shown in the diagram.
Now Router Router A and B are peers of each other. Router A peers with ISP A and Router B peers with Router B.
The issue we have is that Router B knows how to get to router C via eBGP connection to ISP B router or via ISP A, which is advertised via iBGP from Router A.
But ....
Router A only shows in "show ip bgp" about network Router C via ISP A.
If I do a soft clear of bgp information on Router A I then see both paths to Router C via ISP A or ISPB, but once BGP is converged im only seeing best path via ISP A. Can anyone explain why the path via ISP B is not shown on Router A? we are using local preference in a route map to say prefer router A over Router B to exit the network to get to router C.
Synchronisation is disabled. Router A and B are running the same code of IOS and also have similiar configs.
My assumption is that becuase of the local preference Router A stops listing path via Router B in the BGP table. This thought doesnt make complete sense to me ???? In my test lab I always see all paths to exit the AS.
router#show ip bgp 192.168.100.0
BGP routing table entry for 192.168.100.0/22, version 40
Paths: (2 available, best #2, table default)
Not advertised to any peer
65530 64514, (aggregated by 64514 10.x.x.246)
10.x.x.30 from 10.x.x.30 (202.x.x.x)
Origin IGP, localpref 80, valid, external, atomic-aggregate
65530 64514, (aggregated by 64514 10.202.103.246)
10.x.x.22 from 10.x.x.78 (10.x.x.78)
Origin IGP, metric 0, localpref 120, valid, internal, atomic-aggregate, best
Thanks
B
