When does failover occur in an HA cluster?
Applicable Products
- QuTS hero h5.3.0 or later
- High Availability Manager
Overview
In a QNAP high-availability (HA) cluster, a failover occurs when the active node encounters a failure or can no longer continue providing services. In such cases, the passive node automatically takes over the active role to ensure service continuity and availability.
Details
Failover is typically triggered under the following three types of abnormal conditions:
- Connection loss
If the active node's cluster interface becomes disconnected or cannot provide services properly, and the passive node still has a healthy network connection, the system will automatically perform a failover.
- Storage crash
If any storage pool on the active node becomes corrupted, and the passive node's storage pool is either normal or in a degraded state, the system will automatically perform a failover.
- Power interruption
If the active node loses power while the passive node remains powered on, the system will automatically perform a failover.
