elasticsearch cluster_error ai_generated true

MasterNotDiscoveredException: multiple masters detected

ID: elasticsearch/split-brain

Also available as: JSON · Markdown
70%Fix Rate
75%Confidence
3Evidence
2023-01-01First Seen

Version Compatibility

VersionStatusIntroducedDeprecatedNotes
8 active — — —

Root Cause

Cluster split-brain: multiple master nodes elected.

generic

Workarounds

  1. 90% success Ensure odd number of master-eligible nodes (3 or 5)
  2. 88% success Verify network between all master nodes is stable

Dead Ends

Common approaches that don't work:

  1. Kill all master-eligible nodes 90% fail

    Complete cluster outage

  2. Remove minimum_master_nodes setting 88% fail

    Increases split-brain risk