Nordick26 or Anyone,
Hope your out there..
Listen, I came across another BGP issue that doesn't make sense..
Not as complex as my other BGP question..
Router A ----- Router B ---- Our Network..
1. Router A is a stub
2. ISIS running between them
3. iBGP Peering
Router A has a x.x.x.x/19 to advertize to our network..
Router B receives the x.x.x.x/19 route via iBGP considers it as best and inserts it into the routing table.
Router B receives the x.x.x.x/19 network with the next-hop of Router A loopback Addess.
The problem is that Router B does not advertise the x.x.x.x/19 in it's BGP updates with our Network..
The rest of the network doesn't see the /19 network and is unreachable..
So, I remembered what you told me..
"Example: you want to advertise (to external peer) 10.1.1.0/24, which is a summary of 4 subnet's you are using in your AS (10.1.1.0/26; 64/26; 128/26; 192/26). You're receiving this 4 prefixis via iBGP, but in other BGP can advertise this out of you AS, you need to have 10.1.1.0/24 in your routing table. This is why you need to use the static route (pointing back to router you get the more specific route from, or pointing to Null0)."
So, I created a static route to that subnet on Router B pointing to Router A and it worked.. The network see it..
But, why wasn't it propagated throughout the network via BGP??
Router B had an entry in the routing table and considered it as best??