Another important aspect of security is keeping track of compliance. Servers simply won't let you know by themselves whether they're behind on updates, and without some sort of service performing some sort of monitoring, you really won't know what's going on with your servers unless you check.
To solve this problem, Canonical offers a custom service known as Landscape. Landscape allows you to manage your entire fleet of Ubuntu servers from a single page. Landscape will allow you to list any servers that need security updates, automate common tasks, create your own repositories, and more. It presents these features in an attractive user interface. With such a service, it's easy to tell which of your servers need a security update, or a reboot in order to apply a patch.
There are two ways...