On the HP-UX platform, a separate server-process services
each client connection. These processes are dissociated from the
monitor process, so if the monitor terminates or dies, the existing
server-processes servicing client requests will continue to function,
until the client closes the connection, or the server times out.
Normally, the monitor is automatically started up during the
host boot process via a startup script. This startup script is installed
when the HP JDBC product is installed on the server. Normally, the
monitor is never brought down unless the machine is brought down,
in which case it will be automatically stopped via a stop script
that is installed along with the startup script.
If there is a need to start or shut down the monitor when
the host machine is still up and running, the tool monctrl (also installed with the HP JDBC product) can
be used to perform the startup and shut down. The command to use monctrl is:
monctrl {start|reset|kill} [portnumber]
The "start" argument will start up the monitor
on either the default port number or on the specified port number.
The "kill" argument will first terminate each
of the monitor's active child processes, and then terminate
the monitor process itself. Doing this gives a better chance of being
able to restart the monitor once it has been shut down. The portnumber argument is optional, if it is not specified the default
port number will be used.
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 | NOTE: monctrl should only be executed by "root" because
the monitor must run as "root" to allow it to
spawn processes and set user ids. If it is not started by "root," other
users will not be able to connect to the monitor. |
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The "reset" argument is discussed in the
section dealing with the monitor configuration file.
You cannot start a monitor on the same port number as a currently running
monitor. You also can not restart a monitor on its original port number
until all child processes that were spawned by the previous monitor
process are terminated, and the port released. If the monitor is intentionally
terminated or accidentally terminates, all of its child processes
must be terminated before it can be restarted. For this reason,
the monitor must not be terminated by using
the UNIX kill command. Always use the monctrl tool to kill the monitor. The tool will search
out all the child processes and kill them first, before killing
the monitor.
