System and Server Status

The System and Server Status module is a simple but flexible service monitor that provides emailed alerts, scheduled checks, and a status GUI (Figure 15-10). With this module, it is possible to monitor a server and its software to ensure it is operating as expected. The module provides tests for server daemon status, disk usage, CPU load, memory usage, ping response time, file modification, network traffic, and more.

Figure 15-10: System and Server Status

Adding a Monitor

To add a new monitor, select a type of monitor from the drop-down list, and click Add monitor of type. This will open the Create Monitor page (Figure 15-11).

Figure 15-11: Create Monitor

In the preceding figure, you can see that the Description field has been set to Disk Space of /. This is the title that will be displayed on the main page of the module and will be used in any emailed status alerts regarding this monitor. Run on host is set to Local, but if any remote Webmin servers existed in my configuration, it could also check a remote system. Check on schedule? is set to Yes so that if automatic checks are enabled in the module configuration, this monitor will be tested. It is possible to specify commands to be run when the monitor goes down or comes back up, as well as specify on which host the commands will be run. For the Filesystem to check I’ve selected / and specified a minimum free space of 100MB.

Scheduled Monitoring

In order for status checks to be performed regularly (rather than only when you view the module main page), you must enable scheduled monitoring. To do this click on the Scheduled Monitoring button and select Yes for the Scheduled checking enabled? option. Also on this page are options to choose how often checks are performed, days and hours in which checks will be performed, an email address to send status reports to, and under what circumstances an email should be sent.