For years now I have had a successful split tunnel VPN with my Sophos UTM. Recently I’ve wanted to have a full tunnel option for greater security in remote areas (hotel wi-fi, etc.) Unfortunately setting up such a thing in Sophos is NOT straightforward.
The biggest problem I had was that no websites would work after the VPN was initiated. NSlookup was fine, connection was fine, even internal sites would load properly, but no external internet.
Thanks to this post I finally found the culprit: the pesky allowed networks feature for each UTM function. In my case, the VPN was allowing all the necessary traffic through but my transparent proxy was denying web access. I had to add my VPN pool to the list of allowed networks to my proxy.
To summarize, this is what you must do to have a full VPN tunnel:
- Configure the desired method in the Remote Access section. Take note of whatever IP pool you use for your VPN. In my case I used VPN Pool (SSL)
- Ensure that internet access is in the list of allowed networks for the user you’ve configured for VPN (Any, or Internet IPv4/6)
- Add your VPN pool to the list of allowed networks for each service you use.
- Network services / DNS
- Web Protection / Web Filtering