Connecting to the Yale VPN using Linux (Ubuntu)

The Yale VPN uses Cisco AnyConnect.

If Cisco's Linux client works for you, congratulations.  
If, like me, the official client leaves you stranded, then you need to install 
OpenConnect and (assuming you are using Network Manager) the appropriate add-on for the NM applet.

On a Debian-based system, you can type the following command:

$ sudo apt-get install openconnect network-manager-openconnect network-manager-openconnect-gnome

That also pulls in the necessary dependencies (liboath0 libopenconnect2 vpnc-scripts)

Go to NM-applet > Edit Connections > Add > Cisco AnyConnect Compatible VPN (openconnect)

In the tab that opens, add the following information:

Name: Yale VPN
Gateway: access.yale.edu

If you want, you can specify the certificate:
On Ubuntu 14.04, it's

Certificate: /usr/share/ca-certificates/mozilla/GlobalSign_Root_CA.crt

Note: If you use "vpnwindows.yale.edu" as recommended by Yale's ITS website, 
a certificate error will pop up.

The GlobalSign certificate is only valid for:
DNS Name: access.yale.edu
DNS Name: vpn1.its.yale.edu
DNS Name: vpn2.its.yale.edu
DNS Name: vpn3.its.yale.edu
DNS Name: vpn4.its.yale.edu
DNS Name: newvpn.its.yale.edu

Now use the NM applet to connect to the VPN connection you've just created.  A window will pop-up.  

Press the connection button to the right of "access.yale.edu".  

That will take a few seconds to connect, and will then ask you for your NetID and password.

You should have already gotten these from the university.  
Enter them, click "remember password", and you're all set.

You should now be connected to the Yale network.

You can check by going to:

http://ifconfig.me/all

The "remote host" should have "yale.edu" at the end.

This just worked for me in ubuntu 18.04 LTS and access.yale.edu

Lifesaver. A+.