About classful routing.

[speculor_cisco]

I am doing some scenarios with the GNS simulator.

I have added an image of the network.

The configurations are the following:

R0

e1/0: 192.168.1.1/26

e1/1: 192.168.1.65/26

e1/2: 192.168.1.129/26

f0/0: 10.0.0.1/8

R1

f0/0: 10.0.0.2/8

C0

IP address: 192.168.1.2/26

Default gateway: 192.168.1.1

C1

IP address: 192.168.1.66/26

Default gateway: 192.168.1.65

C2

IP address: 192.168.1.130/26

Default gateway: 192.168.1.129

On R0 I have put these commands:

ip route 0.0.0.0 0.0.0.0 10.0.0.2

no ip classless

When I ping 192.168.1.193 from C0, I can see the ICMP traffic out f0/0 interface of R0.

I had understood that with classful routing this type of traffic was discarded.

What do you think?

[Peter Paluch]

Hello,

You probable have CEF activated on the R0. With the CEF, router always performs classless routing and the no ip classless command has no effect. You need to deactivate also the CEF to see the classful routing in effect, so:

no ip cef
no ip classless

Best regards,

Peter

[speculor_cisco]

Hello Peter.

With no ip cef is ok!

Thanks for your answer.