Update CPU microcode

TwinCAT/BSD offers the possibility to update the microcode of a CPU automatically at startup. This allows, for example, the latest security updates to be installed on a system.

This function is disabled by default. Test each update before installing it, as it may affect the system.

Proceed as follows:

1. Install the cpu-microcode-amd or cpu-microcode-intel package with the doas pkg install cpu-microcode-amd or doas pkg install cpu-microcode-intelcommand, dependent on the CPU.

2. Enter ee /boot/loader.conf in the console.
The file loader.conf opens in the editor

kern.geom.label.disk_ident.enable="0"
kern.geom.label.gptid.enable="0"
cryptodev_load="YES"
zfs_load="YES"
hint.attimer.0.clock="0"
vmm_load="YES"
pptdevs="0/30/3"

3. Add the following lines to the loader.conf file:

cpu_microcode_load="YES"
cpu_microcode_name="/boot/firmware/intel-ucode.bin"

4. Restart TwinCAT/BSD with the command shutdown -r now.

With these settings, the system checks for packages with updated CPU microcode at every system startup and automatically installs them if necessary. Remove the two lines from the loader.conf, if this function is no longer desired.