Inter VLAN routing

[admin_2]

I have a 2611 router and 2 1900 switches. I added a 1FE-TX Fast ethernet module to the router. I set up 3 vlans and trunking on the switches connected all of the devices, but cannot route between the vlans.

The vlans are communicating between the switches, as seen by "show vlans" on both switches. But there is no communication with the router. The show vlans on the router also shows the vlans configured.

I used ISL encapsulation on the fast ethernet subinterfaces with no ip address on the main interface. I assigned VLAN 1 as the management vlan with an ip address of 192.168.5.2 on switch 1 and 192.168.5.3 on switch 2, I used 192.168.5.1 on F1/0.1 of the router. I can ping between the switches, but cannot ping the router from the switches or vice versa.

I can ping the all of the subinterfaces from the router itself.The fast ethernet port works fine when used as just a routing interface, but will not work with frame tagging.

Can anyone help?

[Craig Norborg]

How are you routing on the router? Static routes or EIGRP or something?

Can the devices on the various VLAN's ping their default gateway? This should be set to the router's IP on their respective VLAN. Can they ping the IP addresses of the other default gateways?

[#3]

No all of the default gateways for the respective vlans are on the subinterfaces of the fast ethernet port.

[Craig Norborg]

Hmmm... That doesn't really answer any of my questions. Of course the IP's for the gateways are there, where else would they be?

I'll try one more time, how are you routing between the VLAN's? Static routes or a dynamic protocol such as EIGRP?

If you take a device on one of the VLAN's, a computer or something, have you verified that its default gateway corresponds with the IP address assigned to the sub-interface for the VLAN which it is on? Can it ping this default gateway that it has? Can it ping the ip address for the sub-interface of any of the other VLANs?

[aservin]

You do not need EIGRP or any routing protocol, nor static routes because all is direct connected. I would check the conection between the router and the neigborh switch ("sh cdp neig" in the router). Check that the trunking is ok between them.

Do also a "sh ip arp" in the router, if evertything ok you should see the mac-address of the host and the switches, if you see IP address with MAC as incomplete you have a problem with the trunk (or the fisical/logicl path) of the router with the switch.

Check the mac address of the FE of the router, check if in the switch you can see it (show mac-address address )

[degg]

I believe that 1900's only use dot1q encapsulation for trunking, so ISL wont work. Try changing to dot1q and see if that helps.

[degg]

Actually, the 1900 only supports ISL, and not dot1q. I was thinking of the 2950, which supports dot1q but not ISL. My bad.

[Craig Norborg]

Now that I know isn't the case. The 1900 series was out before dot1q trunking was available - only ISL trunking is available on these switches. Its the newer switches (2950 and such) that are dot1q only...