Failover

Failover automatically switches to a standby system when the primary system fails.

What is Failover?

Failover is the automatic switching to a redundant or standby system, server, or network upon the failure or abnormal termination of the primary system.

Failover types

Automatic (no intervention), Manual (requires action), DNS failover, Database failover.

Common misconceptions

"Failover is instant" — Some delay always exists
"Failover is automatic everywhere" — Requires configuration
"Failover equals backup" — Different purposes