VPN Connection Issues with T400/Intel 5300

[chudak]

Hi,

I recently bought a T400 with the Intel 5300 wifi card.

I've been using a T60 to connect to my company vpn (cisco concentrator) and it works fine.

For some reason when I connect with the T400, I have trouble accessing some of the servers on the company network. I'm normally on wifi so I tried connecting to my router with a wired connection and the vpn works like it should (I can access all the machines). Seems like there is some kind of issue with my VPN tunnel when I'm connected with the wifi card.

I'm running Ubuntu 8.10 on both machines using the vpnc client.

Anyone else have any strange experiences using their 5300 wifi card over with a VPN?

Thanks,

Charles

[dk]

I've been using a T400 and Intel 5300 with various post-2.6.27 kernels with OpenVPN. No issues getting and holding a connection.

Have you tcpdump'd the interface when hard wired vs. wifi to see if the packets are even leaving your machine? Since you can connect properly and only some servers are inaccessible it sounds like it may be a routing issue.

[chudak]

Well, hopefully this helps someone else...

Someone on my linux email list at work suggested that it might be an MTU problem. Indeed, I had set my MTU to 1430 at the suggestion of someone on the Ubuntu forums to resolve some wifi speed issues I was having (it didn't help but that was the suggestion).

Changing the MTU back to the default of 1500 made the problem go away! Who'd have thought?

[dk]

Glad you got it sorted out!