I have recently had loads of trouble setting up a Ubiquiti UniFi USG remote user VPN, the USG requires a RADIUS server in order to function correctly, the following article covers this setup freeRADIUS Setup
Once RADIUS is setup the easy part is configuring the USG through the UniFi controller.
- First you will need to login to your UniFi Controller
- Go to the settings
- Then select networks
- Create a new network
- Add a name for the VPN
- Select Remote User VPN for the Purpose
- Enter and IP Address with CIDR e.g. 192.168.10.1/24
- Enter the IP Address for your RADIUS Server
- Enter the port for your RADIUS Server (Default is 1812)
- Enter your RADIUS Servers Secret Key / Password
- Click Save
That is all you need to do!
In version 5.3.11 and below P2TP is not supported which means it will not work with iPhones / iPads etc. this is supposed to be resolved in the next release.