BIG IP Edge Client Linux

The CLI client only supports client cert, username, and password. If you have an OTP you'll have to use the old technique to enter the username and OTP, or password and OTP into the same field and split them on the server-side. But that's a headache you probably should avoid.

Better to use the Linux GUI client by just browsing to the APM VPN endpoint with a stanard web browser (FF or chrome). The setup DEB or RPM packages can be downloaded and installed by following the instructions.