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This guide will help you check for common problems that cause the log ” Master left ; reason ” to appear. To understand the issues related to this log, read the explanation below about the following Elasticsearch concepts: discovery-azure-classic.
Log Context
Log “Master left [{}]; reason [{}]” classname is ZenDiscovery.java.
We extracted the following from Elasticsearch source code for those seeking an in-depth context :
if (localNodeMaster()) {
// we might get this on both a master telling us shutting down; and then the disconnect failure
return;
}
logger.info(() -> new ParameterizedMessage("master_left [{}]; reason [{}]"; masterNode; reason); cause);
synchronized (stateMutex) {
if (localNodeMaster() == false && masterNode.equals(committedState.get().nodes().getMasterNode())) {
// flush any pending cluster states from old master; so it will not be set as master again
pendingStatesQueue.failAllStatesAndClear(new ElasticsearchException("master left [{}]"; reason));
