Auto-Scaling Groups
Auto-scaling groups are Cloudmin's way of scaling up the number of systems that provide some service in response to load. They are typically used when you have multiple virtual systems with identical configurations providing the same service, such as a website, mail server or database replicas. When CPU load or some other metric exceeds a configurable threshold on some or all systems, additional systems are created to handle the load. Conversely, a group can be reduced in size when a second set of thresholds is reached.

This page lists all existing auto-scaling groups, and allows you to create a new one for virtual systems of some type. When adding a group, you can select the maximum and minimum systems in the group, a template for the hostname of new systems, and one or more conditions that control when the group is scaled up (by adding a system) or scaled down.

Each new system in the group is created by cloning an existing template system, in the same way that systems can be manually cloned from within Cloudmin. The exception is Amazon EC2 auto-scaling groups, which create systems from AMIs.

Once a group is created, it will be evaluated periodically by Cloudmin to determine if more or fewer systems are needed. For each group you can control who is notified about group changes, and how often.

Once one or more groups exist, this page can be used to manually scale them up or down, or force immediate evaluation of their scaling rules. For a new group you should typically add at least one system to it with the Scale Up Groups button after creation, so that the rules have a system to work on.