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New Member

VLAN config issues

I have configured a vlan, a 2948 as the vtp server, clients are 2950's 3524xl and 2948's. Configured a sub-interface on the FA port on a 3640 router. All stations on the native vlan can ping the vlan IP ( the 3640) ) but cannot ping or telnet to any devices on the new vlan. All 9 switches are trunking dot1q, all switches see the new vlan. I am assuming I am missing a static route on the 3640 ?


Re: VLAN config issues


What is the Default Gateway on the devices of the new vlan? Is it the

ip address of the 3640 which probably does the intervlan routing?



New Member

Re: VLAN config issues

Check that you have ip routing setup on the router.


Carlos Roque

New Member

Re: VLAN config issues

You may want to confirm your encapsulation on the router sub interfaces match the switch dot1q for 802.1q.

Is the switch port setup as a trunk with the same encapsulation?

If you clear unused VLANs from the trunk, did you add your new vlan to the trunk?


New Member

Re: VLAN config issues

Check your encapsulation on the router interface. Hopefully the 3640 will

support 802.1q. If it is not set or only offers ISL encapsulation you will not

be able to interoperate with 802.1q.

In addition, is the port the router is attached to trunked? If the router is

only connected to a non-trunk port it cannot "see" traffic being trunked

from other VLANs. That would be why only devices on the same VLAN

as the router can access it and no routing is occuring. Also, do you have

sub-intertaces configured with an IP to act as the routing interface for each


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