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Current state of cache key rotation: node -> group name -> status -> encryption key hash.
Administrator initiates process via some kind of user interface(CLI, Visor, WebConsole, JMX, etc).
New key generated using configured EncryptionSPI.
Message with new key(encrypted with master key) is sent by discovery.
On message receive following actions are executed:
Process state: IN PROGRESS.
New key saved in metastore(WAL record about this event is written to the disk).
Further WAL records are encrypted with the new key.
Further page are encrypted with the new key.
Pages reencryption process is initiated.
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