> From the bookie perspective, if a bookie of a ledger ensemble crashes while a > ledger is being written to, then it is replaced and the history of the ledger > is updated in the ledger metadata according to the last add confirmed by the > crashed bookie. If the bookie crashes after the ledger is closed, then > auto-recovery re-replicates the data.
There is one exception to this for the case where the ledger is being actively written to. When the ack quorum is smaller than the write quorum. In this case, when a bookie fails, entries between the point of failure and the point of failure detection will only be replicated |ackQuorum| times, not |writeQuorum| times. Autorecovery should eventually pick this up. -Ivan
