Same subnets

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Feb 19th, 2008
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We encounted a vpn connection problem today, here is the scenario.

Using Cisco VPN client connecting to ASA5510. our VPN address pool is 172.20.1.x/24 and our internal network is 172.16.1.x/24 Now I have staff members in a hotel with their internal network on 17.16.1.x/24. When our staff launch the vpn client it keeps trying to locate the gateway being our VPN gateway.. Is the problem because of the LANS on the same subnet? How can I resolve this?

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Daniel Voicu Tue, 02/19/2008 - 15:27
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Yes, this is a problem created by the overlap of the two subnets.

If you have split-tunneling or "local network" enabled on the config, disable them and have the user try again.

Rate if this helped.



husycisco Tue, 02/19/2008 - 16:34
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Hi Darrin

Either with split-tunnel or tunnelall, problems will persist. Addressing/subneting local network or part of your network, to widely used IP scheme is definetly not the best practise.

Easiest way of solving this issue is simply creating a new VPN IP pool with a subnet which is not widely used by out of the box internet modem/router configs.

For your interal newtork, I would suggest changing to a different octet if possible.




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