fixes #124: Reject cluster join when node identifier is already in use#125
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guusdk wants to merge 1 commit intoigniterealtime:mainfrom
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fixes #124: Reject cluster join when node identifier is already in use#125guusdk wants to merge 1 commit intoigniterealtime:mainfrom
guusdk wants to merge 1 commit intoigniterealtime:mainfrom
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… already in use With the introduction of static, human-configured node identifiers, identifier uniqueness is no longer guaranteed by randomness (OF-3181). Before joining a cluster, the local node now checks whether its configured node identifier is already used by an existing cluster member. If a duplicate is detected, the join is refused to prevent multiple nodes from operating with the same identifier. Additionally, this change causes messages to be logged on standard-out/err when the local node is joining a cluster.
Fishbowler
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Feb 18, 2026
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Looks sensible, but one open query (accidentally attached to the wrong line, but I don't think the line is even relevant to the question)
| for (final Member member : cluster.getMembers()) { | ||
| clusterNodesInfo.put(ClusteredCacheFactory.getNodeID(member), | ||
| new HazelcastClusterNodeInfo(member, cluster.getClusterTime())); | ||
| final NodeID nodeID = ClusteredCacheFactory.getNodeID(member); |
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How do you expect this to behave with 2 booting nodes with the same node ID forming a cluster for the first time?
Does one become the cluster that the other is joining? Or do both reject one another? Is there a difference in terms of how this might affect a production environment?
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With the introduction of static, human-configured node identifiers, identifier uniqueness is no longer guaranteed by randomness (OF-3181).
Before joining a cluster, the local node now checks whether its configured node identifier is already used by an existing cluster member. If a duplicate is detected, the join is refused to prevent multiple nodes from operating with the same identifier.
Additionally, this change causes messages to be logged on standard-out/err when the local node is joining a cluster.