Why does my Amazon OpenSearch Service cluster have more nodes than I originally provisioned?
Last updated: 2021-07-23
In the Monitoring tab of the Amazon OpenSearch Service console, a cluster appears to have twice the number of nodes than originally provisioned. Why is this happening?
Amazon OpenSearch Service uses blue/green deployments to make most cluster configuration changes. During this process, OpenSearch Service provisions a new cluster with the specified number of nodes, copying the entire dataset over from the existing cluster. When the data migration is complete, OpenSearch Service terminates the existing cluster, and the number of nodes returns to normal.
In most cases, the following changes don't trigger a blue/green deployment:
- Access policies
- Automated snapshot hour
- Enabling auto-tune or disabling auto-tune without rolling back changes
- If your domain has dedicated master nodes, changing the data node or UltraWarm node count
For more information about configuration changes and blue/green deployment, see Making configuration changes in OpenSearch Service.