Interesting VPN problem....
First off, greetings. This site has helped me solve nearly every problem I've encountered since my first linux install (Gentoo circa 2006). Kudos!
Unfortunately, I have exhausted all my resources to solve a peculiar vpn problem I've been experiencing in the past few weeks. I need to connect to my university's vpn to ssh into my work computer so I can work at home (baby on the way).
I have a linksys/cisco wrt120n router. I have tried to connect on FC13, openSuse 11.0, and ubuntu 10.04.
The vpn client supplied by the university works fine when running XP on my home network. I can connect to the server and use a windows ssh client to access my computer. However, I cannot connect to the vpn server when running linux. I have tried all the linux vpn clients (network manager, kvpnc, etc...), along with all the mods to iptables and my router I can find on the internet.
I have also tried disabling iptables and my firewall, and I still cannot connect.
What's troubling me is that I can connect to vpn connection using my linux boxes on other LANs, and I can connect perfectly on my home network using windows with the university supplied client. I think the problem is the way linux is communicating with the router. I am a networking noob, so that's as far as I can go with it at this point.
If anyone can help me figure out that is going on, I will gladly buy you a cup of coffee.