Add Standby Node

In a database cluster, standby nodes store a synchronized copy of the primary node’s data. This standby data is kept in sync with the main node so that, in the event of an issue with the primary node, it can automatically take over. This switchover occurs as quickly as possible, minimizing downtime.

Each database cluster can currently support only one standby node.

All Arvancloud database clusters feature automatic failover. When an error affects the primary node, the system will replace it with another node. Without a standby node, however, the restore process can be time-consuming, leading to an extended service recovery time (RTO). The recovery duration will vary based on your data volume; the more data in the cluster, the longer the recovery time. There is also a risk of data loss from the last five minutes.

To address this, enhance availability, and minimize recovery time, we highly recommend adding a standby node to your cluster. With a standby node, the primary node’s failure triggers an immediate switchover, reducing the chance of service disruption or data loss.

Cluster Status	Service Recovery Time	Potential Data Loss
No standby node	Long (depends on data volume)	Last 5 minutes of data
With standby node	Maximum 2 minutes	No data loss

Add Standby Node When Creating Cluster

To add a standby node to a new cluster, simply specify it under the “Standby Node” section during cluster setup.

Please note that standby nodes cannot be added to clusters on the Starter plan.

Add Standby Node After Creating Cluster

If your cluster was initially created without a standby node, you can add one later. From the "All Databases" page, select your desired cluster. In the "Overview" section, click on the "Add Standby Node" button.

Confirm your settings to add the standby node to your cluster.

Remember, clusters on the Starter plan cannot have standby nodes.