This is the first OSPF post I’ll be doing for CCIE lab preparation. Sorry guys, I’ve been slacking with updates. Today I’m posting the tasks, then tomorrow or the day after I’ll post the walkthrough. If any of you work on this before the walkthrough, leave a comment.

Here’s the topology:

Click here for the initial configs

Here are the tasks:
1. Configure R1′s s0/0.102 interface and R2′s s0/0.201 interface in area 12, this area should not receive any Type 5 LSAs. Configure R1′s s0/0.103 interface and R3′s s0/0.301 interface in area 13, R1 should only receive a default route from R3, no other OSPF routes should be in R1′s RIB (from R3). Do not use network statements to accomplish this task.

2. Configure R2, R3 and R4′s ethernet interfaces in area 0. R4 and R5′s serial interfaces should be in area 45. Area 45 should not receive any type 5 LSAs. R5 is an ASBR connected to the internet, it should be the default gateway for the entire OSPF domain.

3. Ensure that all loopbacks are accessible from all routers in the OSPF domain. Ensure that the loopbacks are advertised with their configured masks. Change the OSPF timers on the ethernet segment to be twice as fast as the default.

4. Configure loopback IPs,, and on R3. Inject them into OSPF. These routes should be in Type 5 LSAs. .1.0/24 and .2.0/24 should show a cost of 50, the other two routes’ cost should increment as they travel through the network.

5. Configure the OSPF domain to compensate for gigabit link speeds and calculate cost accordingly. Configure strong authentication between R1 and R3 using the password “cisco”.

Here’s the .net file:
The Dynagen/GNS3 .net file
(you will need to change the paths to make it work)


Colby Glass has been in IT since 2002. He is currently a Systems Engineer (presales) with a Cisco Gold partner and holds the CCNP R/S, CCNP DC, CCDP, CCIP, JNCIA-ER.

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