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Cluster topology is an ordered set of client and server nodes at a certain point in time. Each stable topology is assigned a topology version number - monotonically increasing pair of counters (majorVer, minorVer). Major version is used for tracking grid node events such join, left or fail, minor version is used to track internal events such cache start or activation. Each node maintains a list of nodes in the topology, and it is the same on all nodes for a given version. Topology changes are received by nodes at different times, meaning that at any point in time nodes can see different versions but eventually they will see the same.
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