When read, this variable always returns the most recent value
that it was previously set to. If it has not been set since the
last initialization of the network management subsystem on the node,
it returns a value of `other'.
When set, this variable causes the daemon to undertake the
indicated action:
other - ignored as a no-op
start - attempt to restart the daemon
stop - stop the daemon immediately
stopWhenConvenient - stop the daemon at the next safe checkpoint