Page History

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• INVALID_CLUSTER_ID: The request either included a clusterId which does not match the one expected by the leader or failed to include a clusterId when one was expected.
• FENCED_LEADER_EPOCH: The leader epoch in the request is smaller than the latest known to the recipient of the request.
• UNKNOWN_LEADER_EPOCH: The leader epoch in the request is larger than expected. Note that this is an unexpected error. Unlike normal Kafka log replication, it cannot happen that the follower receives the newer epoch before the leader.
• OFFSET_OUT_OF_RANGE: Used in the FetchQuorumRecords API to indicate that the follower has fetched from an invalid offset and should truncate to the offset/epoch indicated in the response.
• NOT_QUORUM_LEADER: Used in DescribeQuorum and AlterQuorum to indicate that the recipient of the request is not the current leader.
• INVALID_QUORUM_STATE: This error code is reserved for cases when a request conflicts with the local known state. For example, if two separate nodes try to become leader in the same epoch, then it indicates an illegal state change.

Vote

The Vote API is used by voters to hold an election. As mentioned above, the main difference from Raft is that this protocol is pull-based. Voters send fetch requests to the leaders in order to replicate from the log. These fetches also serve as a liveness check for the leader. If a voter perceives a leader as down, it will hold a new election and declare itself a candidate. A voter will begin a new election under three conditions:

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