Ubuntu – Is L2TP over IPsec possible in Ubuntu 16.04 LTS

ipsecnetwork-managervpn

I am trying to connect to a VPN via L2TP over IPsec in Ubuntu 16.04. I know a small handful of posts here and bug reports have begun to document this issue, but I believe my experience, if somewhat naive, may add to the discussion, and perhaps I am overlooking something that may make it work for me.

First, I followed the instructions here to successfully install network-manager-l2tp:
https://github.com/nm-l2tp/network-manager-l2tp

The L2TP option then appeared for the first time in my Add a Connection Type dropdown.

I started a new L2TP connection and entered the IP address, my user name, and my password.

Then I clicked on "IPsec Settings" and entered my shared secret.

When I try to connect to the VPN, I get the error in the upper right corner of the screen "VPN Connection Failed: The VPN connection failed because there were no valid VPN secrets."

I also tried the instructions here, and got the same error: https://github.com/nm-l2tp/network-manager-l2tp/issues/12

I have tried restarting, etc. I do not know what this error means. Thoughts?

Best Answer

Make sure you set the Phase 1 and Phase 2 protocols if your server doesn't properly support auto-negotiation or uses a potentially insecure protocol. You can try 3des-sha1-modp1024 for Phase 1 and 3des-sha1 for Phase 2 (these were common protocols but they are now insecure so don't get attempted automatically).

If you install the ike-scan package you can run sudo ike-scan YOUR.SERVER.IP and it should return at least 1 valid supported protocol. For Meraki Client VPN it is the one I mentioned above.