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- The coordinator decides that a server is dead and initiates recovery. Let's refer to such a master as condemned.
- The condemned server isn't actually dead (perhaps it was temporarily partitioned, or was unable to respond to "ping" requests because of a temporary heavy load, etc.). Let's use the term zombie to refer to such a master; note that not all condemned masters are zombies but, by definition, all zombies are condemned.
- After recovery, a recovery master begins accepting requests for some of the zombie's data, including writes.
- Meanwhile, the zombie continues to serve requests, causing clients to see stale data.
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