If you have multiple servers running with different sets of installed software, it may become cumbersome to regularly check for software updates manually. Webmin allows you to schedule automatic update checking and sends you an e-mail whenever new versions of software become available.
Make sure that Webmin is set up for sending e-mail. Refer to the Enabling Webmin to send an e-mail recipe of this chapter for more information.
To get an e-mail notification when new versions of software become available, perform the following steps:
Navigate to System | Software Package Updates and enable Scheduled checking options.
Set Check for updates on schedule? to check for updates every day and provide an e-mail address to which a report will be sent in case any updates are available. Consider the following screenshot:
cron
is a system utility, which runs in the background as a daemon and starts tasks that are scheduled to execute at a specific time. When Scheduled checking options is enabled, Webmin adds an entry in the system's cron table to execute its update verification script. The cron daemon will then execute the script once every day (hour or week, depending on the setting). If Webmin discovers available updates, it will send you an e-mail.
You could set up Webmin to automatically install the updates when they become available. This may not be as great idea as it seems, because every update can potentially break something on your system. This should not normally happen, but it's a good practice for a human to monitor the update process and verify that everything works as it should after updates have been applied.