Watchdog

Pantavisor also offers some configurable convenience to set up and ping the Linux Kernel watchdog.

Mode

The watchdog mode will determine when the watchdog is pinged by Pantavisor. Set it with the PV_WDT_MODE config key (disabled, shutdown, startup, or always; default shutdown); the ping interval is set separately with PV_WDT_TIMEOUT (seconds, default 15).

Disabled

In this mode, Pantavisor will never ping the watchdog.

Shutdown

This is the default mode. Pantavisor will start pinging the watchdog when a reboot or poweroff order is issued. This way, we make sure the device reboots in a shutdown freeze event.

Startup

This mode combines Pantavisor pinging the watchdog during initialization and shutdown. As the watchdog is activated with a ping, it is expected that a container will take that role during the device regular operation.

Always

In this mode, Pantavisor will ping the watchdog during all the device operation.

Reference

• Configuration — PV_WDT_MODE and PV_WDT_TIMEOUT, with their levels
• Power — the separate suspend/wakelock machinery