VPN tunnels are connected slightly differently on Android phones and Android tablets.
Android phones - Things are easy on phones. On the main screen, simply push the Tunnels button, then do a short tap on the VPN tunnel that you would like to connect.
Android tablets - Things are a little more complicated on tablets. On phones operation of the built-in L2TP client is automatic and behind the scenes. This is not possible on Android 3.x, i.e., on tablets. To connect a VPN tunnel on a tablet, push the Connect button on the main screen. This brings up the built-in L2TP client. Then, using the built-in L2TP client, establish the L2TP connection to localhost that you previously configured according to the section L2TP Configuration. The user name and password that you enter when connecting with the built-in L2TP client are used as follows:
For the interested, here is a quick look at how FEAT VPN invokes the OpenVPN client. If you are not interested, simply skip ahead to the next section Managing A VPN Tunnel.
The following options are passed on the OpenVPN command line in the given order:
errors-to-stderr, which allows FEAT VPN to receive errors from OpenVPN and log them to the FEAT VPN log.
dev-type tun, which forces OpenVPN run in TUN mode. FEAT VPN does not support TAP devices. This is one of the limitations that FEAT VPN inherits from Android's built-in L2TP client.
dev-node <UDS path>, which specifies the simulated TUN device via which FEAT VPN communicates with OpenVPN. FEAT VPN exchanges network packets with OpenVPN via a Unix domain socket.
iproute <executable path>, which specifies the external executable that is used by OpenVPN to communicate things like route updates to FEAT VPN.
setenv, which sets environment variables that are required by the external executable.
socks-proxy 127.0.0.1 1701, which specifies a SOCKS proxy that is part of FEAT VPN. This puts the FEAT VPN app between OpenVPN and the remote OpenVPN server and thus allows the app to manage the connection between OpenVPN and the remote VPN server.
ping-restart 0, which disables restarting the client, if the VPN tunnel is idle. The Internet connection of a mobile device comes and goes and we do not want to restart the client, just because you temporarily have a weak or no signal and cannot talk to the VPN server.
tran-window 28800, which allows up to eight hours without a key renegotiation. Again, this is to prevent the VPN tunnel from being taken down in case your mobile device is temporarily shut off from the VPN server because you have a weak or no signal.
verb 3, which specifies a more verbose log level to be used by default.
askpass <FIFO path>, which specifies the key password. The password is securely passed via a FIFO.
auth-user-pass <FIFO path>, which specifies the user name and password for authentication. The credentials are securely passed via a FIFO.
config <.ovpn file path>, which specifies the VPN configuration file. Note that certain options are stripped from the VPN configuration file when it is loaded. See the Adding and Editing VPN Tunnels section for more information.
When a VPN tunnel is connected, FEAT VPN writes the options that it passes to OpenVPN to the FEAT VPN log.
Once the VPN tunnel connection has been triggered, tablets and phones both automatically switch to the status screen, which is shown in the following screen shot.
The status screen can also be reached by pushing the Status button on the main screen. Pushing the back button of your device takes you back from the status screen to the main screen.
The status screen shows a message that describes the current state of the VPN tunnel. The state message can be any of the following:
Disconnected. No VPN tunnel is currently connected.
Disconnected (Lite time limit). The one hour time limit of FEAT VPN Lite has been reached for the day. In this case, you can only use FEAT VPN Lite again after midnight.
Connected [...]. A VPN tunnel is connected, traffic is being routed through the tunnel, everything is fine. The name of the connected VPN tunnel is given in square brackets.
While connected push the Disconnect button to disconnect the currently connected VPN tunnel. Push Reconnect to disconnect currently connected tunnel and immediately connect it again. Should you experience problems with a connected tunnel after it has been connected for a while, try reconnecting. FEAT VPN tries its best to keep a VPN tunnel connected and stable even in presence of flaky mobile connections and a fluctuating signal. FEAT VPN also tries its best to automatically reconnect a VPN tunnel when you switch, for example, from mobile data to Wi-Fi and back. However, if something goes wrong and FEAT VPN does not do a good job, you can always push the Reconnect button. If you have to do so, then please let us know. Maybe there is a way to make FEAT VPN automatically reconnect also in your specific scenario.
Connecting [...]. A VPN tunnel between FEAT VPN and the OpenVPN server is being negotiated. The name of the VPN tunnel that is being connected is given in square brackets.
Login is not a valid VPN tunnel name. This only applies to Android tablets. As stated above the user name of the L2TP connection established with the built-in L2TP client selects the VPN tunnel to be connected. If a user name is entered that is not the name of a VPN tunnel, this message is displayed. Moreover, a text input field is shown that contains the entered user name. This allows you to correct the user name within FEAT VPN, i.e., without having to return to the built-in L2TP client. When you have corrected the user name, push the OK button to retry with the corrected user name. Push the Cancel button to abort the VPN tunnel connection attempt.
Please enter your key password. The configuration of your VPN tunnel contains a key that is protected by a password. A text input field is shown that allows you to enter the password for unlocking the key, so that the user can be used for authentication with the VPN server. Push the OK button to retry with the entered password. Push the Cancel button to abort the VPN tunnel connection attempt.
Invalid key password. The previously entered password for the password-protected key is invalid and the key could not be unlocked. A text input field is shown that allows you to correct the password for unlocking the key. Push the OK button to retry with the corrected password. Push the Cancel button to abort the VPN tunnel connection attempt.
Note that on Android tablets FEAT VPN initially tries unlocking the key with the password that you entered in the built-in L2TP client when establishing the L2TP connection with FEAT VPN. The shown text input field thus initially contains the password that you entered in the built-in L2TP client.
Please enter your login and password. The VPN server asks you to authenticate with a user name and a password. Two text input fields are shown that allow you to enter your credentials for authentication. Push the OK button to retry with the entered user name and password. Push the Cancel button to abort the VPN tunnel connection attempt.
Invalid login or password. The previously entered user name and password are invalid and authentication with the VPN server failed. Two text input fields are shown that allow you to correct the user name and the password for authentication with the VPN server. Push the OK button to retry with the corrected user name and password. Push the Cancel button to abort the VPN tunnel connection attempt.
Note that on Android tablets FEAT VPN initially tries authenticating with the user name and password that you entered in the built-in L2TP client when establishing the L2TP connection with FEAT VPN. The shown text input fields thus initially contain the user name and password that you entered in the built-in L2TP client.
Connection error. Something unexpected went wrong. Please take a look at the FEAT VPN log for more information and let us know about this in our support forum.