If you wish to connect through your iPhone (or iPad) to a VPN secured by 2FA of ESA, then here are the steps to accomplish.
Configuration of iOS VPN client
Navigate on your device to Settings > General > VPN and click Add VPN Configuration...
For Type select PPTP.
Into the Description field type any desired name by which this connection will be presented in your iOS device.
Into the Server field type the IP address of the server you wish to connect to and into the Account field type your username. Leave the Encryptione Level set to None. The rest of the fields do not need to be set.
Usage of configured iOS VPN client
The usage of configured iOS VPN client is a bit tricky if the VPN is secured via 2FA of ESA. The steps to successfully connect to VPN are as follows:
- Turn on the configured VPN client by tapping the toggle next to Not Connected
- The username is pre-filled due to previous configuration, just enter your password and tap OK
- If the password is ok the login fields will show up again instantly without any error message, while the username will be pre-filled again. At this point you must tap Cancel.
- Turn the configured VPN client on again by tapping the toggle next to Not Connected.
- The username is pre-filled again, but at this point do not enter your password, instead you enter the One Time Password (OTP) you received via sms or generated via ESA mobile application. After entering the OTP tap OK.
- If you entered a valid OTP, then at this point you should see the active connection of your VPN client