INE Workbook Vol 1 IP Routing part 2

I'm going to skip a fancy intro and just get to the nitty-gritty details.....

You can handle recursive GRE routing lookups using distribute-list on the routing protocol or static routes with lower AD.You would need to filter the destinations for the GRE tunnel out through the distribute list. So say on router 1...

int tunnel1
tunnel source lo0
tunnel dest 150.1.4.4
!
router rip
distribute-list prefix R4 out
!
ip prefix-list R4 deny 150.1.4.0/24
ip prefix-list R4 permit 0.0.0.0/0 le 32


You would obviously need to repeat this on the opposite end of the tunnel interface. Even easier, you can add static routes (with a lower AD) and the tunnel by default will use the static routes instead of any dynamically learned routes.Unfortunately, this is most likely not going to be available to you in the lab.

Also, to debug ip routing, you need to enable 'no ip route-cache' in the transit path.This enables fast-switching so that you can actually see the packets.

You can use a GRE tunnel in conjunction with a backup interface. Simply create a tunnel across the frame relay interface with unique IP addressing. And by enabling keepalives on the tunnel interface across the frame relay, these routers will be able to detect if IP transport is lost instead of relaying FREEK or PVC status. Also, by enabling backup interface on tunnel, the router will switch to the backup interface if there are any failures in the end-to-end transit of the frame relay PVC.

With ODR, CDP is enabled on ptp interfaces by default.You would need to enable CDP on multipoint interfaces. Man, I need to remember the simple command 'router odr'. For some reason, I'm always looking for an interface level command...most likely because of it's dependence on CDP.

I was going to include OER within this post, since it is covered in the same workbook but due to it's size, I will create a new post regarding OER. The INE labs are good, but I'm having some difficulty when it comes to Dynamips. One word of wisdom - make sure your 3725 router in dynamips has at least 256mb of memory. OER did NOT work on a 3725 with 128mb of ram.

Up next...OER