Re: VPN through NAT?

On 08/13/06 09:21, Troy Settle wrote:
Probably not the best list to ask this on, but it's the closest that I'm subscribed to...

I have several customers who use VPN (Windows PPTP) to connect to their Corporate networks. The first was sitting behind NAT on a FreeBSD router. The PPTP did not work. I moved them out of NAT and onto a regular IP, and it worked fine. I then swapped out the FreeBSD box with a Cisco 2620 and again tried the PPTP via NAT, but still it wouldn't work.

Another customer is behind a Cisco 804 and his PPTP also did not work when his network was behind NAT, so I have to assign a static subnet for him.

From home, sitting behind NAT on my Netgear router, I can turn up PPTP connections all day long. What gives with FreeBSD and Cisco's implementation of NAT that PPTP doesn't want to work?

Thanks,



I'm no expert on the subject, but I recall hitting this in the past and reading about passing GRE packets through, along with a couple of ports to forward to the VPN endpoint.

Eric


--
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Eric Anderson Sr. Systems Administrator Centaur Technology
Anything that works is better than anything that doesn't.
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