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It may happen that on the primary node at the time of receipt of the request , processing the distribution on the version of the topology topology version N + 1 is already relevant .or in the process of changing to what version.

If next version is not compatible with previous (having the same partition assignment) In this case, a response is sent to the near node indicating that a more current recent version of the topology is usedacutal and transaction should retry on next version. This process is called remap.

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First, each enlisted key is assigned on the update sequence number using ,  generated by next value of HWM counter field.

Then primary node builds a backups map (dht map) and sends prepare requests to the backup nodes, if any, containing enlisted keys and their update numbers.

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