org.apache.hadoop.hdfs.server.protocol (Apache Hadoop HDFS 3.5.0 API)
Description: declaration: package: org.apache.hadoop.hdfs.server.protocol

# Package org.apache.hadoop.hdfs.server.protocol

@LimitedPrivate("HDFS") @Evolving package org.apache.hadoop.hdfs.server.protocol

- Class
  Description
  BalancerBandwidthCommand
  Balancer bandwidth command instructs each datanode to change its value for the max amount of network bandwidth it may use during the block balancing operation.
  BalancerProtocols
  The full set of protocols used by the Balancer.
  BlockCommand
  A BlockCommand is an instruction to a datanode regarding some blocks under its control.
  BlockECReconstructionCommand
  A BlockECReconstructionCommand is an instruction to a DataNode to reconstruct a striped block group with missing blocks.
  BlockECReconstructionCommand.BlockECReconstructionInfo
  Block and targets pair
  BlockIdCommand
  A BlockIdCommand is an instruction to a datanode regarding some blocks under its control.
  BlockRecoveryCommand
  BlockRecoveryCommand is an instruction to a data-node to recover the specified blocks.
  BlockRecoveryCommand.RecoveringBlock
  This is a block with locations from which it should be recovered and the new generation stamp, which the block will have after successful recovery.
  BlockRecoveryCommand.RecoveringStripedBlock
  BlockReportContext
  The context of the block report.
  BlocksStorageMoveAttemptFinished
  This class represents, the blocks for which storage movements has done by datanodes.
  BlockStorageMovementCommand
  A BlockStorageMovementCommand is an instruction to a DataNode to move the given set of blocks to specified target DataNodes to fulfill the block storage policy.
  BlockStorageMovementCommand.BlockMovingInfo
  Stores block to storage info that can be used for block movement.
  BlocksWithLocations
  Maintains an array of blocks and their corresponding storage IDs.
  BlocksWithLocations.BlockWithLocations
  A class to keep track of a block and its locations
  BlocksWithLocations.StripedBlockWithLocations
  CheckpointCommand
  Checkpoint command.
  DatanodeCommand
  Base class for data-node command.
  DatanodeLifelineProtocol
  Protocol used by a DataNode to send lifeline messages to a NameNode.
  DatanodeProtocol
  Protocol that a DFS datanode uses to communicate with the NameNode.
  DatanodeRegistration
  DatanodeRegistration class contains all information the name-node needs to identify and verify a data-node when it contacts the name-node.
  DisallowedDatanodeException
  This exception is thrown when a datanode tries to register or communicate with the namenode when it does not appear on the list of included nodes, or has been specifically excluded.
  DropSPSWorkCommand
  A DropSPSWorkCommand is an instruction to a datanode to drop the SPSWorker's pending block storage movement queues.
  FencedException
  If a previous user of a resource tries to use a shared resource, after fenced by another user, this exception is thrown.
  FenceResponse
  Response to a journal fence request.
  FinalizeCommand
  A BlockCommand is an instruction to a datanode to register with the namenode.
  HeartbeatResponse
  InterDatanodeProtocol
  An inter-datanode protocol for updating generation stamp
  InvalidBlockReportLeaseException
  This exception is thrown when a datanode sends a full block report but it is rejected by the Namenode due to an invalid lease (expired or otherwise).
  JournalInfo
  Information that describes a journal
  JournalProtocol
  Protocol used to journal edits to a remote node.
  KeyUpdateCommand
  NamenodeCommand
  Base class for name-node command.
  NamenodeProtocol
  Protocol that a secondary NameNode uses to communicate with the NameNode.
  NamenodeProtocols
  The full set of RPC methods implemented by the Namenode.
  NamenodeRegistration
  Information sent by a subordinate name-node to the active name-node during the registration process.
  NamespaceInfo
  NamespaceInfo is returned by the name-node in reply to a data-node handshake.
  NamespaceInfo.Capability
  NNHAStatusHeartbeat
  NodeRegistration
  Generic class specifying information, which need to be sent to the name-node during the registration process.
  ReceivedDeletedBlockInfo
  A data structure to store the blocks in an incremental block report.
  ReceivedDeletedBlockInfo.BlockStatus
  RegisterCommand
  A RegisterCommand is an instruction to a datanode to register with the namenode.
  RemoteEditLog
  RemoteEditLogManifest
  An enumeration of logs available on a remote NameNode.
  ReplicaRecoveryInfo
  Replica recovery information.
  ServerCommand
  Base class for a server command.
  StorageBlockReport
  Block report for a Datanode storage
  StorageReceivedDeletedBlocks
  Report of block received and deleted per Datanode storage.
  VolumeFailureSummary
  Summarizes information about data volume failures on a DataNode.