ZOOKEEPER-4882: Fix data loss after rejoin and restart of a node experienced temporary disk error #2268
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…rienced temporary disk error The cause is multifold: 1. Leader will commit a proposal once quorum acked. 2. Proposal is able to be committed in node's memory even if it has not been written to that node's disk. 3. In case of disk error, the txn log could lag behind memory database. This way, node experienced temporary disk error will have hole in its txn log after re-join. Once restarted, data will loss. This commit complains the lag so to reload disk database to memory. This way, the node will not be able to become leader and sync missing txns from leader. Refs: ZOOKEEPER-4882, ZOOKEEPER-4925
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The cause is multifold:
This way, node experienced temporary disk error will have hole in its txn log after re-join. Once restarted, data will loss.
This commit complains the lag so to reload disk database to memory. This way, the node will not be able to become leader and sync missing txns from leader.
Refs: ZOOKEEPER-4882, ZOOKEEPER-4925