To ensure self-reliance related to the system performance within a virtual machine, you can add a virtual Watchdog Timer (VWDT) device. If the guest operating system stops responding and cannot recover on its own due to software glitches or errors, the VWDT waits for a predefined period of time and then restarts the system.

You can enable the VWDT to start either by the guest operating system, or by the BIOS or EFI firmware. If you chose the VWDT to start by the BIOS or EFI firmware, it starts before the guest operating system boots.

The VWDT has an important role in guest-based clustering solutions where each virtual machine in the cluster can recover on its own if it fails.