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Since BookKeeper ledgers can be written only once, if another Broker starts the recovery process and opens the ledger for reading it, automatically fences the previous writer so as to allow no more writes on that ledger. Thus, in case of leadership change, for instance in case of temporary network failures, the 'past' leader Broker is no longer able to log entries and, as a consequence, cannot 'change' anymore the global status of the system in memory.
Tailing the Log and Replicating System Status
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