OSPF Summarization Discard Route

Written by Rene Molenaar on 20 September 2011. Posted in OSPF

Scenario:

Ever since you encountered a router your quest has been to become a succesful network engineer. Your career is prosperous and there isn't a bit that you haven't slain before. This time however you are running into trouble with one of your OSPF routers. It seems one of your routers is installing a null0 route whenever you do summarization and this is something you don't want to happen...

Goal:

All IP addresses have been preconfigured for you.
Configure OSPF and use the correct areas.
Configure a loopback0 interface on router Spielburg with network address 3.3.3.3 /24.
Configure router Shapeir to summarize network 3.3.3.0 /24 to 3.0.0.0 /8.
Configure router Shapeir so it doesn't add a null0 entry in its routing table.

IOS:

c3640-jk9s-mz.124-16.bin

Topology:

OSPF Summarization Discard Route Network Topology

Video Solution:

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Related Articles: ICND1 Assesment Lab
Static Routing Beginners Lab
OSPF Single Area
OSPF Intermediate
OSPF Virtual Link and Summarization

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Comments (11)

baloo247
2011-09-26 13:36:19

hi, the config file on this one is the type7 translate config. Can you update please.

ReneMolenaar
2011-09-26 22:55:52

I'll upload it next time, left it at the office and i'm not there this week ;D

Bal
2011-09-27 04:13:28

Thanks rene, just keeping you informed. I built the lab myself, was easy enough.

jithuts1
2012-04-29 06:36:14

hi,, try to download

narangi
2012-08-21 12:14:48

gud lab, thnks rene

Subunit
2012-09-17 17:29:14

i redistributed a static route and summarized it at the ASBR.
no null0 interface and proper network advertised into area 0
so there was an easier way than redistribution... thanks for the tip Rene.

ArcanjoV8
2012-09-20 16:35:30

Very interesting. Thank you!

rathinikunj
2012-10-30 17:09:25

There can be a minor correction.
4th Goal says "Configure router Shapeir to summarize network 3.3.3.0 /24 to 3.0.0.0 /8."

This means Shapeir router should have a 3.3.3.0/24 route but it is getting a /32 route. In order to get a 3.3.3.0/24 route on Shapeir router below should be configured on the Spielburg route:

inter loopback0
ip ospf network point-to-point
end

waseem
2012-11-03 11:20:14

its not working

pintu_sarkar
2012-12-24 08:35:56

Thanks a tonnnnnnnnnnnnnnnnnnnnnnnnnn

m3g9tr0n
2013-01-23 12:00:04

The following command is the main goal of this lab

Shapeir(config)#router ospf 1
Shapeir(config-router)#no discard-route internal

Master CCNA

Master CCNP SWITCH

Master CCNP ROUTE

Master CCNP TSHOOT