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New Member

Unable to understand this routing table created by RIP

I am attaching packet tracer file "Routing Rip Example.pkt". in which i connected few routers and configured networks using two classe of IPs, Class C and ClassA all using same subnet mask /24,pis is here http://i.lulzimg.com/1b225f6042.png and  the problem is Router0's routing table has entry 10.0.0.0/8 like this http://i.lulzimg.com/ce24f3ec3a.png , why there is only one entry of 10's network having /8 entry despite of i have two 10's network configured /24 ??

8 REPLIES
Purple

Unable to understand this routing table created by RIP

Hi,

if you want to see both 10's /24 networks you'll have to:

-enable rip v2 on r2:

router rip

ver 2

- disable auto-summarization

router rip

no auto

then on r0: clear ip route *  and sh ip route rip will show you the /24 networks.

Regards.

Alain

Don't forget to rate helpful posts.
New Member

Re: Unable to understand this routing table created by RIP

Hi,

the reason is, that RIPv1 will summmarize your networks at a class-full boundary, which means that a Class-A network will always get a /8. This is a internal process on your Router because RIPv1 does not send any Subnetmasks within it's updates.

So,

your router is getting a update for a network 10.0.0.0 (<- without any subnetmask) and will assign a /8 automatically, because 10.0.0.0 is in the Class-A range.

Using RIPv2 would solve the problem

Cadet Alain explained how to configure it!

regards

BTW: Please rate, if helpful!

regards, Dirk (Please rate if helpful)
New Member

Unable to understand this routing table created by RIP

@cadet alain and @Dirk Woellhaf

Thanks for your replies..however my problem doesn't see to get solved, here is the example to Networks topology along with the networks ID in the pic

http://i.imgur.com/GYzUp.png

The Routing table of router1 is as follows

http://i.imgur.com/iJdGs.png

Here all is good, all subnet of 10's are showing along with /24 mask, which i configured in real, neither i used rip v2, nor disabled summarization...

Unable to understand this routing table created by RIP

Hi,

ad  "Here all is good, all subnet of 10's are showing along with /24 mask, which i configured in real, neither i used rip v2, nor disabled summarization..."

You can see the 10's routes as connected here, NOT received by RIP.

That's why the subnet mask is correct!

HTH,

Milan

New Member

Unable to understand this routing table created by RIP

How about Router2's routing table which has exactly same entry like Router1

Unable to understand this routing table created by RIP

Are you running the same IOs version on all your routers?

Which one?

HTH,

Milan

New Member

Unable to understand this routing table created by RIP

(C2800NM-ADVIPSERVICESK9-M), Version 12.4(15)

Purple

Unable to understand this routing table created by RIP

Hi,

here it is not the same output as one route is directly connected and the other learnt via RIP.

You got the correct /24 mask because you configured the same mask everywhere so the router is considering the mask of the IP address configured on the interface where the RIP update is coming.

Regards.

Alain

Don't forget to rate helpful posts.
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