Setting up your supported LTE modem

If your modem is on the supported modems list and it is an LTE modem you can use the information in this section to set it up. Its sometimes difficult to determine if FortiOS sees your modem as an LTE modem, so if the following doesn't work you could try setting it up as a PPP modem.

Connect your modem by plugging it into the FortiGate USB slot. The modem will power up and once it starts, if the modem is supported its name should appear in the Modem field in the Wireless Modem section of the Network > Modem page.

If your modem is an LTE modem, use the following command to enable LTE support:

config system lte-modem

set status enable

end

If your LTE modem is supported, entering this command should allow your LTE modem to connect to your wireless provider's network. Check the LEDs in your modem (if any) to verify that it has connected.

To verify that FortiOS recognizes your LTE modem, go Network > Interface and verify that the wwan interface is visible on the interface list and its Status is up. If your wireless provider supports DHCP, the modem may have already connected to your wireless provider's network and the wwan interface will have an IP address and the FortiGate will have received other network settings such as DNS servers and your wireless provider's default route.

If the wwan interface is not up and connected you may need to configure additional LTE settings.

Allowing traffic to use the LTE modem

To allow communication to the internet through the LTE modem, add firewall policies for the wwan interface. For example, to allow users on your internal network to connect to the internet through the LTE modem, create internal to wwan policies.

If you are using your LTE modem for a backup or redundant internet connection, you can add an SD-WAN interface that includes the FortiGate wired internet connecting interface and the wwan interface.

Additional LTE modem configuration settings

If the wwan interface does not appear or if it doesn't come up, you may need to adjust some LTE modem settings. The following options are available:

config system lte-modem

set status {disable | enable}

set extra-init <init-string>

set authtype {none | pap | chap}

set apn <string>

set modem-port

end

where

extra-init allows you to enter an extra initialization string required by some LTE or WIMAX modems.

authtype {none | pap | chap} set to none by default. If your wireless provider requires you to authenticate, select the required authentication method (pap or chap) and add a username and password.

apn allows you to enter an APN string if required for your modem.

modem-port set to 255 by default. Set a different modem port as required by some modems.

If these settings do not allow your LTE modem to connect, you may have an unsupported modem.