Apple Mac OS X Server (Version 10.6 Snow Leopard) - Manual (Page 173)

Chapter 8 Monitoring Your System 173
A green status indicator shows the component is OK, a yellow status indicator notes a
warning, and a red status indicator notes an error.
Server Monitor works for Xserves only. For more information about Server Monitor,
choose Server Monitor Help from Server Monitor’s Help menu.
Using RAID Admin for Server Monitoring
Like Server Monitor, you can configure RAID Admin to send a mail or a page when a
component is in trouble. For every unit, RAID Admin displays the status of the unit and
each of its components, including disk drives, fibre channel, and network connections.
RAID Admin uses green, yellow, or red status indicators. You can also configure it to
send you a mail or a page when a component is in trouble.
In addition, RAID Admin provides you with an overview of the status of the Xserve
RAID units that appear in the main window.
For more information about RAID Admin, choose RAID Admin Help from RAID Admin’s
Help menu.
Using Console for Server Monitoring
Use Console to monitor relevant log files for potential problems that might cause your
server to fail.
For example, you can monitor your web server’s /var/log/httpd/access_log file for
signs of denial of service (DoS) attacks. If you detect these signs, you can immediately
implement a planned response to prevent your web server from becoming
unavailable.
To improve your log monitoring efficiency, consider automating the monitoring
process using AppleScript or Terminal commands like
grep and launchd .
Using Disk Monitoring Tools
Running out of disk space can cause your server to become unreliable and probably
fail. To prevent this from happening, you must constantly monitor disk space usage on
your servers and delete or back up files to clear disk space.
Mac OS X Server ships with a number of command-line tools to monitor disk space on
your computer:
 df . This command tells you how much space is used and how much is available on
every mounted volume.
For example, the following command lists local volumes and displays disk usage: