pfSense LTE WAN on APU3/APU4

This is a step-by-step tutorial for setting up LTE WAN on pfSense 2.4. This tutorial will work for the following modems:

  • Simcom SIM7600G-H
  • Quectel EC25-E
  • Huawei ME909s-120
  • Huawei ME909u-521
  • Number of other modems

Step 0: connect your hardware properly

You can connect 2 LTE modems to APU3/APU4 boards, but typically you will use only one.

Connect your modem to the middle mPCIe port  and your SIM card to SIM 1 port (refer to the image).

If you want to connect 2 modems, you will have to install the operating system on SD card. The first mPCIe port is shared between SATA drive and LTE modem. 

If you decide to use the first mPCIe slot (mSATA), you must enable EHCI0 controller in BIOS. Otherwise the modem won't be detected.

The last mPCIe is intended for WiFi. Modem won't work in this port because it's not wired to a SIM slot (it will be detected though)

WARNING: make sure you use a new BIOS version (from 2019 or newer). Older BIOS versions had opposite wiring of SIM to mPCIe slots. SIM 1 was connected to the first mPCIe slot instead of the middle one.


Step 1: Install pfSense

Installation of pfSense is covered by a separate article. Follow the pfSense installation instructions and come back.

Step 2: Add boot delay

Note: This step is only necessary for some modems such as Huawei.

Huawei takes about 20 seconds to fully initialize and be detected by the operating system. You must add a boot delay in the operating system to allow enough time for the modem to initialize. We recommend setting the loader_delay variable to 40 seconds.

Boot the operating system and edit /boot/loader.conf


Note, there is another configuration variable called "autoboot_delay". This is something else. Don't confuse these two.

See the video to the right for more details.

Step 3: setup PPP interface in pfSense

Login to the web UI, go to "interfaces"->"Assignments"->PPPs->"Add"



PPP configuration fields:

Link Type: PPP

Link Interface: is different for different modems. For Huawei it's  /dev/cuaU0.0 for Quectel it's /dev/cuaU0.3

Note: If you only see /dev/cuau0 and /dev/cuau1 in this list, it means that your modem is not detected. Try rebooting the router.

Access Point Name (APN): ???

Note: You can select Country, Provider and Plan, this will populate the Phone number and APN fields, but remember that these values can be incorrect!

APN field depends on your provider. Try googling "Provider APN". For example, "Tele2 APN".
For Tele2 in Sweden the APN is "".

Phone number: *99# (this is almost always the same)

Init string: &F

Note: your provider may require different, special init string. Different modems also accept different commands. "&F" is a minimal working init string. If you leave this field empty, pfSense will use default "AT&F&C1&D2E0S0=0M1" which won't work.

If you have a PIN set on your SIM card, fill that in. If you don't leave it empty.


Step 4: Assign PPP interface as WAN

Once the PPP is created, go to Interfaces->Assign and select PPP in place of your old WAN.


Step 5: verify that it works

if the stars aligned just right, you should have internet connection through LTE now. The WAN interface should show a green arrow up on the dashboard.


If something went wrong, go to the LTE troubleshooting page.

Good luck!

Tip: check out many similar articles about LTE in our Knowledge Base.

TekLager specializes in selling open source hardware for building routers, firewalls and other network appliances.


wle200nx wireless WiFi kit

TekLager Compex wle200nx wireless WiFi kit for routers. Qualcomm Atheros AR9280. Works well with pfSense
356 SEK 2099-01-01 356 SEK
445.00 SEK incl. vat

APU2D0 Router and 802.11ac 3×3 MIMO Access Point

TekLager OpenWRT router, 5 Ghz access point
2,358 SEK 2099-01-01 2,358 SEK
2947.50 SEK incl. vat

APU4C4: 4x Gigabit LAN, Quad Core CPU, 16GB SSD, 4GB RAM

TekLager APU4C4 Router/Firewall. 4x Gigabit NIC, Quad Core CPU, 16GB SSD, 4GB RAM. Compatible with pfSense, IPFire, OPNSEnse and others.
2,387 SEK 2099-01-01 2,387 SEK
2983.75 SEK incl. vat

TLSense i7 6500U: 6x Gigabit LAN, 6th gen i7 CPU, 128GB SSD, 16GB RAM

TekLager TLSense i7 6500U: 6x Gigabit LAN, 6th gen i7 CPU, 128GB SSD, 16GB RAM
6,618 SEK 2099-01-01 6,618 SEK
8272.50 SEK incl. vat