Sambar Server Watcher Daemon

Sambar Server Documentation

Watcher Daemon

While Sambar Technologies takes all crashes very seriously, the most important consideration is the availability of the WWW server. Therefore, the Sambar Server Watcher Daemon was developed to monitor the Sambar Server and ensure that it is always running.

The Watcher Daemon can be run either when running the Sambar Server as a windows GUI (bin\server.exe) or when running as an NT Service (bin\ntserver).

Important: The Watcher Daemon does not run by default. The Watcher Daemon can be configured to run through the Sambar Server administration interface. The Watcher Daemon should not be started manually.

The Watcher Daemon performs a www-ping of the server every 30 minutes (configurable) and if the server does not respond, it is terminated and restarted. A log of all actions taken is written to the log/watcher.log file.

The following [server] configuration parameters are used by the watcher:

Run Watcher	true or false
Watcher Timeout	# (seconds)
Watcher Server	server.exe
Watcher Notify	webmaster@foobar.com
Watcher SMTP	Mail server to use to send out watcher notifications. If left blank, the value of the "SMTP Server" parameter will be used. This should NOT be the local Sambar server as you will not recieve notifications if the server is down.

The Watcher Daemon connects to the Sambar Server via the localhost address (127.0.0.1). In the event of a WatcherLog failure, a message is written to the log\watcher.log file.

In addition, if the Watcher Daemon restarts the Sambar Server and the Watcher Notify parameter is configured, e-mail will be sent to the administrator indicating the server was either successfully restarted or could not be restarted and is down. Note: The e-mail notification feature is only available with Sambar Server Pro.

DrWatson Use
Ken Johanson noted that DrWatson will often display a pop-up window that will prevent the Watcher Daemon from restarting the server in the event of a crash. When using the Sambar Server in a production environment, Windows NT users should uncheck the "Show Visual Alert" option in Dr. Watson, as this may interfere with the Watcher Daemon's attemts to restart the server in the event of a server crash.