An occasional health checkup will improve a computer system's service and extend its useful life.

There are six steps to a basic health checkup for a Unix/Linux server but before starting the checkup run the vmstat system utility program.

vmstat is a Unix/Linux command that displays the status of the virtual memory kernel plus some other useful system statistics. It can be run by typing 'vmstat 5' which will display one line of data every 5 seconds until it is canceled.

I recommend that you run vmstat for a 24 hour period and save the information into a file. This can be done by typing 'vmstat 1200 > /tmp/vmstat.data.'

After the 24 hours has elapsed cancel the command. The file /tmp/vmstat.data will contain three lines of output for each of the 24 hours.

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