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Community Member

ISDN DDR - VPN connectivity problem

Hi all,

I'm trying to connect a Win2k server at my house (behind a Series 800 ISDN router, obtains dynamic IP addy) to my work network (static addresses, win2k VPN server mapped to static address).

What I've encountered is being able to connect only one way (allows me to reach work network from my server at home -OR- allows me to reach home network from VPN server at work - NOT both at the same time, which I would like, so that I can connect my laptop to the Exchange server).

I have tried something similar to this ( but with allowing port 1723 and GRE through ("access list 101 permit GRE any any" and then "ip access-group 101 in" under Dialer1). I can get everything else (www, ftp, etc.) to work through the router but not PPTP VPN.

I have read that you cannot use PAT with GRE tunnels - but I also read that GRE tunnels only work with the IP Plus feature pack, which I don't have and costs $75.

The only way I can get it to work (I think) is by statically mapping my dynamically obtained IP addy from my ISP to my win2k server at home - this is a real pain because my ISP has an 8 hour session limit, so it resets the IP. (I can get a static IP but it's more $$ and my ISDN line and ISDN service are already twice as much as a cable modem/DSL line - unfortunately neither are available where I am).

I appreciate any help!



Community Member

Re: ISDN DDR - VPN connectivity problem

If you are running NAT with VPN, you will need some sort of NAT traversal, which I don’t believe your hardware is going to accomplish. Take NAT out of the picture and you should be in business.

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