Connecting to the Multitech Conduit

First step to configure your Multitech Conduit for a cellular connection is to add a GSM configuration and to test it, to make sure it works right.

For this, you will need access to a terminal. On Linux or macOS, you can use a regular terminal.

Connect to your Multitech Conduit, by one of these two ways:

• If your gateway is already connected via Ethernet and you know the local IP address of your gateway, you can connect via SSH, by typing ssh root@<ip-address>.
• Otherwise, we'll connect using the debug port of your Multitech. Open up the front facade of your Conduit with a screwdriver, plug a microUSB cable in, and plug the other end in a USB port of your machine:
  
  
  
  In your terminal, find the name of your device. On macOS machine, it will usually be in the form /dev/tty.usbmodem<id>. Try using the ls /dev command to find out what's the name of your device.
  
  Once you have it, type the command screen <device-name> 115200 to connect to the Conduit. For example, for me, it was the command screen /dev/tty.usbmodem1421 115200 that allowed me to connect. The Conduit will ask your for a login and password. Unless you have already changed it, it should be root and root. Don't forget to change them!

At this point, you're connected to the Multitech Conduit!

Configuring the cellular connection

Now that you're connected, you have to do some configuration.

Configuring the APN

1. You first need to look for your network provider's APN. For example, for us (T-Mobile NL), it was smartsites.t-mobile. Every network provider has a different APN - but usually an online search will give you the APN quickly.
2. In the terminal, type: mlinux-set-apn <APN>. The terminal will indicate you that the APN was successfully configured.

Configuring the PPP options

We're now going to configure the PPP configuration. PPP is the name of the driver that allows a Linux machine to connect to a cellular network, using a modem.

To edit those files, you'll need to use a CLI-based text editor, such as vim, cat or nano. If you've never used one before, we recommend using nano: it's the easiest one to learn, and the closest to graphical text editors.

1. First, copy the old /etc/ppp/options file to a backup file: mv /etc/ppp/options /etc/ppp/options_old
2. Create the options file: nano /etc/ppp/options
3. Add only these lines:
   /dev/modem_at0
   debug
   logfile /var/log/pppdlogs
4. Save the file.

Configuring the modem chat

We're now going to configure the modem chat. The modem chat is what PPP will send to the Conduit's modem to establish a connection.

1. Copy the old /etc/ppp/peers/gsm_chat file to a backup file: mv /etc/ppp/peers/gsm_chat /etc/ppp/peers/gsm_chat_old
2. Create a new file: nano /etc/ppp/peers/gsm_chat
3. Add this to the file:
   ABORT 'NO CARRIER'
   "" 'AT'
   OK 'AT+CMEE=2'
   OK 'AT+CSQ'
   OK 'AT+CPIN=<pin>'
   OK 'AT+CGDCONT?
   OK 'AT+CGREG?'
   OK 'ATD*99***1#'
   CONNECT ''
   
4. Don't forget to replace <pin> with the PIN code of your SIM card!
5. Save the file.

Your cellular connection is now configured!

Testing the cellular connection

It's now time to test your connection.

1. Start the ppp daemon: pppd debug call gsm
2. Follow the progress of the connection by typing tail -f /var/log/pppdlogs -n 30.
3. Once the "replacing old default route" line has appeared, it means the connection was successful, and that the Conduit is using the cellular connection as a default connection!

You can then test your connection by pinging different servers: ping 8.8.8.8, ping 4.2.2.1... If you get a response, then you're all set!

Start cellular connection on boot

Now that we have tested our connection, it's time to configure ppp so that it starts automatically on boot.

1. Open the /etc/ppp/ppp_on_boot file: nano /etc/ppp/ppp_on_boot
2. There will be a "$PPPD call provider" line. Change it to "$PPPD call gsm".
3. Save the file.
4. In the terminal, type this command: update-rc.d ppp defaults.
5. Reboot the device, and after a minute or so, test your connection with ping 8.8.8.8.

If it all goes well, you should now be connected!