Cassandra: hinted handoff in case of multiple nodes down

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Cassandra uses the concept of hinted handoff for consistency. It means that if a node is down, the coordinator takes note of it and waits till it's up, and then resends the write request to it.

Does it mean that Cassandra sends success response back to the client even while it's waiting for the unavailable node to be up? If yes, then what if all of the target nodes were down? Won't it mean a successful response to the client even without a single write?

cassandra
1 Answers

Hints are not stored if consistency cannot be acheived

For example consider you have 3 replicas and all nodes are down. In this case if write consistency is quorum then hints will not get stored and write will fail. Hints get stored only when one node is down and coordinator got success response from two nodes.

Only exception is write consistency ANY. In this case even if all replicas are down hint will get stored and write will be successful.

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