Minimum master nodes above quorum
discovery.zen.minimum_master_nodes is higher than the majority needed for master-eligible nodes. After master node loss, the cluster might refuse to elect a new master even when enough nodes remain.
For a complete list of insights, refer to AutoOps insights.
| Field | Value |
|---|---|
| Component | Elasticsearch |
| Severity | Low |
| Scope | Cluster |
| Domains | configuration, high-availability, stability |
The following is an example of what you might see when this insight is triggered. Real insights use live data and links from your deployment or cluster.
discovery.zen.minimum_master_nodes is es-data-01. The cluster has 12 master-eligible nodes.
AutoOps shows different recommendations depending on how their conditions match your deployment or cluster.
Set minimum master nodes quorum
Condition: Always shown for this insight.
Set discovery.zen.minimum_master_nodes to 2 in each node's config, then rolling-restart master-eligible nodes so the quorum takes effect.
discovery.zen.minimum_master_nodes is the legacy Zen discovery quorum setting for older clusters. Modern Elasticsearch manages voting configuration automatically, but this value might still be set on legacy or upgraded clusters.
The safe value is half of master-eligible nodes, rounded up. When the setting is higher than that majority, losing one or more master-eligible nodes can block master election even though a real quorum of nodes is still available. The cluster might stay unavailable until you lower the setting or restore enough master-eligible nodes.