17. Autoscaling groups

Glossary

Autoscaling group: An autoscaling group manages multiple instances of the same resource (for example, servers), based on need. For instance, when there is a lot of internet traffic to a site, the autoscaling group can start more servers. When there is less traffic, the autoscaling group can reduce the number of servers.

Best Practice

• It is recommended that an autoscaling group spans more than one availability zone, for reliability.
• If we set the autoscaling group to run one resource, it will run that one resource in one of the availability zones.
• If there is a failure of that resource, the autoscaling group will shut it down in that availability zone and start that same resource in the other availability zone.