EIGRP

[carl_townshend]

Hi all, if im joining 2 networks together, say one router is 192.168.1.1/30 and the other 192.168.1.2/30, would I need to addvertise this 192.168.1.0/30 network on both routers for them to be able to route other networks between them ?

thanks

[answanso]

First of all those networks are the same, so its not really different networks.

192.168. 1.00000000

255.255.255.11111100

192.168. 1.00000001 <- First host .1

192.168. 1.00000010 <- Last host .2

192.168. 1.00000011 <- Broadcast .3

With Routing Protocols such as EIGRP and OSPF you are enabling the interface to participate in the routing protocol and not "advertising" a network per say. Don't get me wrong, you are advertising routes, I just think you are looking at this wrong. The network command enables an interface to participate.

If you have:

192.168.1.5/30-rtr1-192.168.1.1/30--192.168.1.2/30-rtr2

Under rtr1 you would have something like this:

router eigrp 10

no auto

network 192.168.1.1 0.0.0.0

network 192.168.1.5 0.0.0.0

Under rtr2 you would have something like this:

router eigrp 10

no auto

network 192.168.1.2 0.0.0.0

This configuration basically says the interfaces with .1, .2, and .5 participate in eigrp. The result will be rtr2 will have an eigrp learned route for .4/30 and a directly connected for .0/30. rtr1 will have two directly connected routes for .0/30 and .4/30.

So to answer your questions eigrp must be enabled on any interface you want to participate in eigrp.

HTH

Anthony

[imranmohd]

Hi

You can configure ur router in the following way

R1

network 192.168.1.1 0.0.0.0

no auto-summary

R2

network 192.168.1.2 0.0.0.0

no auto-sumar

But as you said networks betwn these two routers....i didnt get it.bcoz both the routers are connected point to point with CIDR of /30.In /30 you have only two valid ips 1 & 2.

if you have other networks connected to other interfaces , you will have to advertise those networks using network commnd.