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Overlapping IP address ranges on VPN

Level 1
Level 1

I need to create a new site to site VPN where the address range on the new site is The problem is that I already have this same range on a WAN connection, which the Pix knows about due to the "route inside" statement. I don't believ that the alias command will work in this scenario. Does anybody have any ideas how this can be done?

1 Reply 1

Jon Marshall
Hall of Fame
Hall of Fame

You could NAT the IP addresses before they enter the VPN at the remote end.

If the traffic is only ever intiated from the new site you could hide all the addresses behind one IP address which would need to be routable back to the new site.

If traffic needs to be initiated both ways then you'll need to set up one to one translations for the addresses. Again the translated addresses used would need to be routable back to the new site.

Here's a link to a Cisco doc on Overlapping Networks


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