High Availability

High availability is a way of setting up hosting so that no single failure takes your site offline.

Instead of running on one server, a site might run across several synchronized ones. That way, if one machine dies, the others keep answering requests and most visitors never notice.

High availability is how you push a more reliable uptime, and it's a common requirement for sites where an outage means lost revenue or reputation. It costs more than a single server, so it's a tradeoff you weigh against how much downtime you can tolerate.