unable to ping

[axfalk]

A very simple setup: a 2600 router, with one interface patched into a 2950 switch and the other interface patched into a 3550 switch. Both switches have vlan1 as their management vlan. We have defined vlan2 on both switches and configured a couple of ports on vlan2 on both switches. When we patched both routers' interfaces into the ports on vlan2 on the corresponding switches, a pc that was patched into a vlan2 port on the 2950 switch was unable to ping a pc patched into a vlan2 port on the 3550 switch.

Does this make sense, or are we missing something?

thanks.

[sevans1979]

Did you change the router interfaces to the same subnet as VLAN2? If the ethernet interfaces are still in the subnet as VLAN 1 then you will not have connectivity to VLAN 2's subnet. Also make sure that the VLAN 2 ports and the pc's on VLAN 2 are in the same IP subnet.

Keep me posted!

please rate if this reply helps

Scott

[axfalk]

thanks for your response. unless i am missing something, the 2 router interfaces can't be on the same ip subnet and since both of them patched into the vlan 2 ports, i made the address of the fa0/0 int to be 172.21.72.113/21 and fa0/1 to be 10.46.24.254/24.

Thanks again.

[axfalk]

by the way, if i patched both interfaces and the 2 PC's into the vlan1 ports, it works OK.

thanks again

[sevans1979]

I believe you are correct...sorry, its to early for me.

Try this thou. Get a crossover cable and form a trunk between the two switchs. Use will have to use dot1.q encapsulation b/c the 2950 does not support ISL. This trunk will extend the vlans over the two switchs.

Please rate if this helps

Scott

[sevans1979]

When you change the two pc to the VLAN 2 ports are you changing the PC IP address to the VLAN 2 subnet??

Scott

[sagittarius]

Whats the Default Gateway on the PC's ...it should be the Router interface IP's ....Have you enabled ip routing on router. Can u ping the Router interface from PC on the same subnet ...

[axfalk]

the Default Gateway on the PC's is their corresponding Router interfaces' IP addresses and I can ping the default gateways from their corresponding PC's.

Thanks

[h.parsons]

can you ping from a pc connected to the 2950 to the gateway address of the pc on the 3550?(the router interface connected to the 3550)

[Josef Oduwo]

Perhaps it would better if you drew us a diagram - even a MS Paint sketch will do, along with show vlan and your show run outputs for all boxes.

Cheers,

Josef.

[sevans1979]

Have you tried implementing static route's in your router configs? Making sure that all hosts have routes to and from each subnet?

[tekha]

Just to be sure, have configured both interfaces on the switches as trunks or are they "dynamic desirable"?

Would it be possible for you to post the config of the 2 switches?

[stephen.oliver]

I believe the following happens. The ping leaves the first PC. It hits the router which routes it to the other interface and sends it out. The ping hits the 2nd switch but since the ping has no vlan info on it the switch assumes it is a VLAN 1 packet and forwards it to VLAN 1 ports. The second pc is in vlan 2 so it doesn't see the packet. Change the management vlan on both switches to vlan 2.

Hope this works, Stephen.

[stephen.oliver]

Ignore my wrong reply above. I misread the question and saw some trunking reference.

Stephen.