RouterBoard: RB953GS-5HnT-RP (Because I need 2 WiFi interfaces AND a slot for the LTE card.)
LTE Card: Sierra Wireless MC7411 (Verizon certified, and activatable with no tricks.)
Auxiliary WiFi Card: Mikrotik R11e-2HPnD
I'm not going to go into all the configuration details of my router, just the important ones for getting the LTE going.
LTE Card Configuration
Before inserting the MC7411, connect it to a PC. (MiniPCIe to USB adapters are readily available on Amazon for under $20.) I used Linux. If you're on Windows, then use whatever terminal client you prefer. Run these commands:
The commands do the following, respectively:
* Gets a serial prompt to the card's AT command interface.
* Enables privileged commands. The default password is "A710". YMMV.
* Locks the USB interface to USB 2.0 mode.
* Enables MBIM mode, and the diag, nmea, modem, and mbim feature sets.
* IMPORTANT! Tells the card to clear its existing cellular configuration and start from scratch.
Insert the card into your RouterBoard and power it up.
Set the configuration as follows:
You should be all set! If your SIM is activated, enabling the interface should cause it to connect almost immediately. Don't forget to add appropriate masquerade rules and such, as you would for any other WAN interface.
/interface/lte/set [ find default-name=lte1 ] allow-roaming=yes apn-profiles=verizon
IMPORTANT: If you find that your LTE modem keeps disconnecting every few seconds, add this firewall rule to the top of your firewall configuration to make the tower happy:
chain=output action=reject reject-with=icmp-port-unreachable connection-state=invalid protocol=tcp out-interface=lte1