umb(4) is a kernel driver for USB MBIM devices.

MBIM devices establish connections via cellular networks such as GPRS, UMTS, and LTE. They appear as a regular point-to-point network interface, transporting IP frames.

Required configuration parameters like PIN and APN have to be set with umbctl(8). Once the SIM card has been unlocked with the correct PIN, it will remain in this state until the MBIM device is power-cycled. In case the device is connected to an "always-on" USB port, it may be possible to connect to a provider without entering the PIN again even if the system was rebooted.

For more information, please refer to the umb(4) and umbctl(8) manual pages.

Thanks to the Makefiles provided, the following command should be sufficient to build both the kernel module if_umb.kmod as well as the user-land configuration tool umbctl:

$ make

The following command should be sufficient to install both the kernel module if_umb.kmod as well as the user-land configuration tool umbctl:

$ make install

A manual page is available for the user-land configuration tool, umbctl:

$ man ./sbin/umbctl/umbctl.8

It is possible to create a package for direct deployment onto OPNsense:

$ make package

This will create a package called os-umb-$VERSION.txz in the plugin/umb/work/pkg folder. This can then be installed in OPNsense directly:

# pkg add os-umb-$VERSION.txz