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We need to close down an old VPN server which is going end of life at the end of April. A replacement VPN server is already available, and switching over to it just requires updating the OpenVPN configuration file on your device. The OpenVPN software itself does not need to be updated. Most people are already using the new VPN server. We are contacting people who need to update their config file directly by email.

Do I need to update my configuration?

Start up the VPN on your device and go to https://apps.ch.cam.ac.uk/vpn/vpn-test to find out.

I need to update, where can I download the new configuration file?

More detailed instructions for setting up OpenVPN

Troubleshooting

Two common post-update issues are covered below. If you are having any other VPN-related problems please see our VPN troubleshooting page.

Problems with journal access

The old VPN server configuration was a 'full tunnel' ie all the network traffic goes via the VPN and appears to the world to be coming from the Chemistry department. This can be very slow if you're using videoconferencing apps, so we now provide a 'split tunnel' configuration by default where only traffic intended for the University network goes via the VPN, and everything else goes direct. However some online journals still check if a connection is coming from the University and refuse access if it's not, although this is getting rarer. If you have trouble accessing journals with the split tunnel VPN configuration then we have alternative full tunnel confguration files for the new server:

It's possible to have both sorts of configuration file on a machine and choose which one you want when you start the VPN; just give them different names.

Dealing with the warning: 'apparent public IP address was not different after connecting' on Macs

This is a warning, not an error. It happens because in Chemistry and SPRI we now configure the VPN to use a 'split tunnel' ie to only send network traffic destined for the University of Cambridge over the VPN link. All other traffic goes direct to its destination. This setup gives the best network performance for videoconferencing, while still allowing you to access University-only resources. It is less private than using a 'full tunnel' which is why Tunnelblick warns about it. There are two ways to avoid the warning:

  • Disable the IP address checking feature using the checkbox on the "Preferences" panel of Tunnelblick's "VPN Details" window.
  • Switch to using a 'Full Tunnel' configuration file. This will send all your network traffic via Chemistry's network when the VPN is on and may be slower. Full tunnel configuration can be downloaded from https://downloads.ch.cam.ac.uk/vpn/latest/mac/chemistry-full-tunnel.tblk...

It's possible to have both sorts of configuration file on a machine and choose which one you want when you start the VPN; just give them different names.