BGP / OSPF – Redistribute-internal
You connected BGP with OSPF
then you enter command for Redistribute the route in each BGP / OSPF. You found out that OSPF didn’t learn the BGP router.
- You have double checked Network advertised in BGP & OSPF
- in BGP and OSPF, also Redistribute on BGP & OSPF on BGP 2 Router.
- You checked “Show ip bgp topology * ” on BGP 2, you can see Routing, OSPF Need to learn.
- You have enter “debug ip routing”, to see Update routing information
SHOW TCP BRIEF
BGP routing is differenet than other routing protocol. RIP, OSFP, EIGRP they are using multcast to advertise routing.
BGP is using TCP port 179, to establish bgp neighbour relationship and advertise route. Once BGP neighbour is establish.
when you type “show tcp brief”, you will see as bellow, The state, ip address of BGP.
By Default, IBGP will not advertisted the route to IGP. The reason being is, to avoid routing loops.
in order to advertise BGP routing to OSPF, by Entering “BGP REDISTRIBUTE-INTERNAL” at Router BGP2
BEFORE BGP REDIS
AFTER BGP REDIS
After the commands is entered.
As we enter debug ip routing before, we can see routing update information on router OSPF, as image above.
Show ip route -> this time we can see Routing advertise from BGP.
Also we have a successful ping from BGP1 loopback to OSPF Loopback.
