IP addressing Question (GNS3)

Magik SmokeMagik Smoke Posts: 9Registered Users ■□□□□□□□□□
I’m running three virtual routers (2691’s with NM-4Ts). The topology looks like this:
6ek9iq.jpg
All serial interfaces are on the same subnet, 192.168.0.0 (/24).
R1 S1/0 = 192.168.0.1 255.255.255.0
R2 S1/0 = 192.168.0.2 255.255.255.0
R2 S1/1 = 192.168.0.3 255.255.255.0
R3 S1/1 = 192.168.0.4 255.255.255.0

R1 can ping 192.168.0.1, 192.168.0.2
R2 can ping 192.168.0.1, 192.168.0.2, 192.168.0.3, 192.168.0.4
R3 can ping 192.168.0.2, 192.168.0.3

My problems:
1) R3 can’t ping its own local interface 192.168.0.4 or the far side interface 192.168.0.1.
It can ping all interfaces on R2.

2) R1 can’t ping the second interface on R2 but it can ping its local interface 192.168.0.1.

Am I missing something simple here? Everything is on the same subnet and the results themselves seem inconsistent.
Any help would be much appreciated.

Comments

  • marhomarho Posts: 14Member ■□□□□□□□□□
    Hello,

    you can't assign IP addresses from same subnet to different interfaces on 1 router (in this case router R2), therefore you must use another IP subnet (for example 192.168.1.0/24) on one serial link.

    Martin
  • Magik SmokeMagik Smoke Posts: 9Registered Users ■□□□□□□□□□
    Hi Martin,

    I adapted (simplified) the topology from a Chris Bryant "Trainsignal" video. He was using a "Hub and Spoke" topology and no routing... all devices on the same subnet and pinging across a frame switch.

    It's possible I missed something with his setup/configs? I'll review the lab again.

    Thank you.
  • networker050184networker050184 Posts: 11,962Mod Mod
    Hi Martin,

    I adapted (simplified) the topology from a Chris Bryant "Trainsignal" video. He was using a "Hub and Spoke" topology and no routing... all devices on the same subnet and pinging across a frame switch.

    It's possible I missed something with his setup/configs? I'll review the lab again.

    Thank you.

    Well, if you want to go with that topology you are going to need a frame switch also.
    An expert is a man who has made all the mistakes which can be made.
  • Magik SmokeMagik Smoke Posts: 9Registered Users ■□□□□□□□□□
    Well, if you want to go with that topology you are going to need a frame switch also.

    /me smacks head

    I've forgotten too much since the last time I took a cisco exam.
    Thank you, that was the issue.
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