EIGRP Summarization without Null0

Where is the solution to this config...I'd like to verify my work.

Hi Damone,

It's not here yet, i'm focusing my time at this moment to build new labs.

Let me give you a little hint though...what options do you have to ensure something does not show up in your routing table? Don't think about security stuff. Think in the line of "infinity metric" or a............ ........

Rene

I feel like i'm doing something wrong.. this lab was almost too?..
I disabled auto-summary and created a summary route on fa0/0 for 1.0.0.0 255.0.0.0

no null0 route installed? ;P

Am I missing the point?

Hi Matthew,

When you create a summary for EIGRP on an interface your router should install a null0 route by default. Is the summary working and advertised?

The key to the lab is creating a summary without the null0...;D Anything you did wrong perhaps?

I'll do it one more time and report back

I'll post my configs too!

I have completed this by adding static route to the summarised one. So, router prefers static route compared to eigrp summary and it removes null 0 from routing table. Still it is advertising summary route to it's neighbors.

Am I correct in this???

@sudheer you are on the right track, and yes it is ok. I'm not fond of the static/default route option because you can fix about anything with those....so I changed the goal to prohibit static/default routes. What else can you think of? ;D

Hi everyone,

i am so new on this site and briefly it is perfect. i was studying for this topology but no result. is there anywhere that you put solutions ?

Hello Rene,

I'm a bit confused over the solutions I have read for removing the Null0 route. May be the solutions I have read are incorrect but if the answer is 255 are we not creating a potential routing loop situation? If we remove the Null0 route then within Hollywood routing table Bollywood is the source of the summary route. the 255 solution removes the Null0 route from the local routing table but it still advertises that route to Bollywood. May be I have misconfigure something that stops this situation. But when I remove loopback0 and I trace to 1.1.1.1 I have a immediate routing loop.

Hi Guys,

I try to have a video+final configuration for each lab, at the moment there's about 50% of videos...going to get to 100% in December

About the routing loop...yes that's something to be aware of. The null0 entry is normally installed to ensure your router doesn't forward packets if it doesn't know where to send them. If you don't want to see the null0 entry you have to change the administrative distance to 255.

It's definitely not something you are going to do on a real network, I added this lab because I encountered it on a CCIE lab. You are vulnerable to routing loops for sure ;D

Rene

Hi Rene Molenaar,

i had completed the lab and after just adding no auto summary in eigrp NULL0 Entry got removed from routing table of Hollywood. is it what ur excepting in the lab.

Hi Kedar,

It's not what I was looking for I added the video to this solution on Youtube, you can see it there. I'll add it to this article later today.

Rene