What is the proper way to shutdown the Vault?

The proper way to shutdown the Vault is to briefly push the power button or choose a “shutdown” option from within the operating system that is running on the Vault. The system will then shutdown in an orderly manner (as long as the Operating System allows and is configured for this functionality). Simply pulling the power cord or removing power could result in a corrupt file system and/or erratic behavior at the next reboot.

Specific to pfSense CE, a brief push and release of the power button will shut the system down.