Not enough masters to ack sent cluster state – How to solve this Elasticsearch exception

Opster Team

August-23, Version: 6.8-7.15

Briefly, this error occurs when there are not enough master-eligible nodes available to acknowledge the sent cluster state. This could be due to network issues, node failures, or configuration problems. To resolve this, you can increase the number of master-eligible nodes, check your network connectivity, or adjust the ‘discovery.zen.minimum_master_nodes’ setting to a lower value. Also, ensure that your nodes are properly configured and functioning correctly.

This guide will help you check for common problems that cause the log ” not enough masters to ack sent cluster state. ” to appear. To understand the issues related to this log, read the explanation below about the following Elasticsearch concepts: cluster, discovery.

Log Context

Log “not enough masters to ack sent cluster state.” class name is We extracted the following from Elasticsearch source code for those seeking an in-depth context :

 this.clusterState = clusterState;
 this.publishResponseHandler = publishResponseHandler;
 this.neededMastersToCommit = Math.max(0; minMasterNodes - 1); // we are one of the master nodes
 this.pendingMasterNodes = totalMasterNodes - 1;
 if (this.neededMastersToCommit > this.pendingMasterNodes) {
 throw new FailedToCommitClusterStateException("not enough masters to ack sent cluster state." +
 "[{}] needed ; have [{}]"; neededMastersToCommit; pendingMasterNodes);
 this.committed = neededMastersToCommit == 0;
 this.committedOrFailedLatch = new CountDownLatch(committed ? 0 : 1);