When launched by the init.d script, pdns_server
wraps itself inside a 'guardian'. This guardian monitors the
performance of the inner pdns_server
instance which shows up in the process list of your OS as
pdns_server-instance
.
It is also this guardian that pdns_control
talks to. A STOP is interpreted by the guardian,
which causes the guardian to sever the connection to the inner process and terminate it, after which it terminates itself.
The init.d script DUMP and SHOW commands need to access the inner process, because
the guardian itself does not run a nameserver. For this purpose, the guardian passes controlsocket requests to the control console of the
inner process. This is the same console as seen with init.d MONITOR.