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ISA500, L2L-VPN with overlapping subnets

Dear All!

We want to configure a L2L-VPN with an ISA550 and a ASA5515X. The challenge is, that on the ASA side the subnet of the ISA side is in use. So we have to do a "NAT before VPN" on the ISA550 side to a transfer subnet The tunnel itself between the 2 firewalls is working fine, but I've difficulties with the NAT on the ISA550.

Here a short overview of the (planed) traffic flow between the subnets: <--> ISA 550W <--> NAT to <--> VPN-Tunnel <--> ASA 5515X <-->

So access from clients on the ISA-side 192.168.1.x to have to be natted to 10.11.14.x and this traffic should be routed into the VPN-Tunnel. As I said, the tunnel (between and itself is up, but I have troubles configure this NAT.


Thanks, Woger

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