Site to Site VPN IP Addresses

[kirby449]

Hi Guys

Just a quick question - with a site to site PIX VPN is it necessary to have different internal IP address subnets on the sites to be connected. For example, if one site has a 192.168.1 network, does the other site have to be on a different subnet?

We have 2 networks to join together and they are on the same subnet and it would be a bit of a pain to alter one of them. There are about 150 network devices in one site and 50 in the other.

Cheers
Kirby

 

[themut]

No it is not necessary... in your case you have to NAT both ends.

 

[kirby449]

Thanks Themut for the info - could you elaborate please.

Much appreciated
Kirby449

 

[themut]

Check out the link below it is an excellent guideline:

http://www.cisco.com/en/US/tech/tk583/tk372/technologies_configuration_example09186a00800949f1.shtml

It explains how to set up a VPN between two networks using the same private IP address range. On one site there's a PIX and a VPN concentrator on the other end, pay attention to the PIX end.

 

[kirby449]

Thanks Themut! Just the job!!

Cheers