Lab 3 - reachability

I'm working on Lab 3, and I'm having problems with reachability. To be more specific, BB1 knows nothing about my internal network ( - there are no "network" commands in R6's initial config, which means it doesn't advertise the network to BB1.

At first I thought this was just another troubleshooting task, but... right now I'm not so sure how to solve this.

I tried announcing the network from R6 via BGP:


router bgp 100

 network mask

 aggregate-address summary-only

However, this has a very nasty side-effect - it automatically installs a route to Null0, which practically prevents the router from reaching half of the network (it no longer uses the default route).


Rack1R6#sh ip ro

Routing entry for

  Known via "bgp 100", distance 200, metric 0, type locally generated

  Redistributing via ospf 1

  Advertised by ospf 1 subnets

  Routing Descriptor Blocks:

  * directly connected, via Null0

      Route metric is 0, traffic share count is 1

      AS Hops 0

What would be the recommended way to solve this issue? 


[ Later edit: same problem with BB2 - the lab asks us to send it a default route via RIP (and the solution even checks for this route!), but the config for BB2 has "distribute-list prefix DENY_DEFAULT in" on RIP. Which once again means that BB2 knows nothing about my network... ]




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