Automatic Takeover of a Cluster

Configure the cluster to automatically recover from an abrupt total cluster failure.

Automatic cluster takeover is triggered if an instance attempts to connect to the cluster and:

You have enabled automatic cluster takeover.
The quorum device indicates the cluster is running, but the instance detects no heartbeat.

The automatic cluster takeover configuration parameter enables the instance attempting to connect to the cluster to form a new cluster, starting the cluster coordinator and recovering the databases. The syntax for automatic cluster takeover is:

sp_configure "automatic cluster takeover", [1 | 0]

Setting the value to 1 (the default) to enable the automatic cluster takeover; set to 0 to disable automatic cluster takeover.

In environments that have I/O fencing enabled, automatic cluster takeover is guaranteed to be a safe operation. For environments that do not have I/O fencing, a malfunction of the algorithm may introduce data corruption. This configuration parameter disables the algorithm if it malfunctions. There is always a risk of data corruption in environments without I/O fencing, and disabling automatic cluster takeover does not mitigate all of those risks.