|
@@ -0,0 +1,408 @@
|
|
|
|
+~~ Licensed under the Apache License, Version 2.0 (the "License");
|
|
|
|
+~~ you may not use this file except in compliance with the License.
|
|
|
|
+~~ You may obtain a copy of the License at
|
|
|
|
+~~
|
|
|
|
+~~ http://www.apache.org/licenses/LICENSE-2.0
|
|
|
|
+~~
|
|
|
|
+~~ Unless required by applicable law or agreed to in writing, software
|
|
|
|
+~~ distributed under the License is distributed on an "AS IS" BASIS,
|
|
|
|
+~~ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
|
|
+~~ See the License for the specific language governing permissions and
|
|
|
|
+~~ limitations under the License. See accompanying LICENSE file.
|
|
|
|
+
|
|
|
|
+ ---
|
|
|
|
+ HDFS Commands Guide
|
|
|
|
+ ---
|
|
|
|
+ ---
|
|
|
|
+ ${maven.build.timestamp}
|
|
|
|
+
|
|
|
|
+HDFS Commands Guide
|
|
|
|
+
|
|
|
|
+%{toc|section=1|fromDepth=2|toDepth=4}
|
|
|
|
+
|
|
|
|
+* Overview
|
|
|
|
+
|
|
|
|
+ All HDFS commands are invoked by the <<<bin/hdfs>>> script. Running the
|
|
|
|
+ hdfs script without any arguments prints the description for all
|
|
|
|
+ commands.
|
|
|
|
+
|
|
|
|
+ Usage: <<<hdfs [--config confdir] [COMMAND] [GENERIC_OPTIONS]
|
|
|
|
+ [COMMAND_OPTIONS]>>>
|
|
|
|
+
|
|
|
|
+ Hadoop has an option parsing framework that employs parsing generic options
|
|
|
|
+ as well as running classes.
|
|
|
|
+
|
|
|
|
+*-----------------------+---------------+
|
|
|
|
+|| COMMAND_OPTION || Description
|
|
|
|
+*-----------------------+---------------+
|
|
|
|
+| <<<--config confdir>>>| Overwrites the default Configuration directory.
|
|
|
|
+| | Default is <<<${HADOOP_HOME}/conf>>>.
|
|
|
|
+*-----------------------+---------------+
|
|
|
|
+| GENERIC_OPTIONS | The common set of options supported by multiple
|
|
|
|
+| | commands. Full list is
|
|
|
|
+| | {{{../hadoop-common/CommandsManual.html#Generic_Options}here}}.
|
|
|
|
+*-----------------------+---------------+
|
|
|
|
+| COMMAND_OPTIONS | Various commands with their options are described in
|
|
|
|
+| | the following sections. The commands have been
|
|
|
|
+| | grouped into {{{User Commands}}} and
|
|
|
|
+| | {{{Administration Commands}}}.
|
|
|
|
+*-----------------------+---------------+
|
|
|
|
+
|
|
|
|
+* User Commands
|
|
|
|
+
|
|
|
|
+ Commands useful for users of a hadoop cluster.
|
|
|
|
+
|
|
|
|
+** <<<dfs>>>
|
|
|
|
+
|
|
|
|
+ Usage: <<<hdfs dfs [GENERIC_OPTIONS] [COMMAND_OPTIONS]>>>
|
|
|
|
+
|
|
|
|
+ Run a filesystem command on the file system supported in Hadoop.
|
|
|
|
+ The various COMMAND_OPTIONS can be found at
|
|
|
|
+ {{{../hadoop-common/FileSystemShell.html}File System Shell Guide}}.
|
|
|
|
+
|
|
|
|
+** <<<fetchdt>>>
|
|
|
|
+
|
|
|
|
+ Gets Delegation Token from a NameNode.
|
|
|
|
+ See {{{./HdfsUserGuide.html#fetchdt}fetchdt}} for more info.
|
|
|
|
+
|
|
|
|
+ Usage: <<<hdfs fetchdt [GENERIC_OPTIONS]
|
|
|
|
+ [--webservice <namenode_http_addr>] <path> >>>
|
|
|
|
+
|
|
|
|
+*------------------------------+---------------------------------------------+
|
|
|
|
+|| COMMAND_OPTION || Description
|
|
|
|
+*------------------------------+---------------------------------------------+
|
|
|
|
+| <fileName> | File name to store the token into.
|
|
|
|
+*------------------------------+---------------------------------------------+
|
|
|
|
+| --webservice <https_address> | use http protocol instead of RPC
|
|
|
|
+*------------------------------+---------------------------------------------+
|
|
|
|
+
|
|
|
|
+** <<<fsck>>>
|
|
|
|
+
|
|
|
|
+ Runs a HDFS filesystem checking utility.
|
|
|
|
+ See {{{./HdfsUserGuide.html#fsck}fsck}} for more info.
|
|
|
|
+
|
|
|
|
+ Usage: <<<hdfs fsck [GENERIC_OPTIONS] <path>
|
|
|
|
+ [-move | -delete | -openforwrite]
|
|
|
|
+ [-files [-blocks [-locations | -racks]]]
|
|
|
|
+ [-showprogress]>>>
|
|
|
|
+
|
|
|
|
+*------------------+---------------------------------------------+
|
|
|
|
+|| COMMAND_OPTION || Description
|
|
|
|
+*------------------+---------------------------------------------+
|
|
|
|
+| <path> | Start checking from this path.
|
|
|
|
+*------------------+---------------------------------------------+
|
|
|
|
+| -move | Move corrupted files to /lost+found
|
|
|
|
+*------------------+---------------------------------------------+
|
|
|
|
+| -delete | Delete corrupted files.
|
|
|
|
+*------------------+---------------------------------------------+
|
|
|
|
+| -openforwrite | Print out files opened for write.
|
|
|
|
+*------------------+---------------------------------------------+
|
|
|
|
+| -files | Print out files being checked.
|
|
|
|
+*------------------+---------------------------------------------+
|
|
|
|
+| -blocks | Print out block report.
|
|
|
|
+*------------------+---------------------------------------------+
|
|
|
|
+| -locations | Print out locations for every block.
|
|
|
|
+*------------------+---------------------------------------------+
|
|
|
|
+| -racks | Print out network topology for data-node locations.
|
|
|
|
+*------------------+---------------------------------------------+
|
|
|
|
+| -showprogress | Print out dots for progress in output. Default is OFF
|
|
|
|
+| | (no progress).
|
|
|
|
+*------------------+---------------------------------------------+
|
|
|
|
+
|
|
|
|
+* Administration Commands
|
|
|
|
+
|
|
|
|
+ Commands useful for administrators of a hadoop cluster.
|
|
|
|
+
|
|
|
|
+** <<<balancer>>>
|
|
|
|
+
|
|
|
|
+ Runs a cluster balancing utility. An administrator can simply press Ctrl-C
|
|
|
|
+ to stop the rebalancing process. See
|
|
|
|
+ {{{./HdfsUserGuide.html#Balancer}Balancer}} for more details.
|
|
|
|
+
|
|
|
|
+ Usage: <<<hdfs balancer [-threshold <threshold>] [-policy <policy>]>>>
|
|
|
|
+
|
|
|
|
+*------------------------+----------------------------------------------------+
|
|
|
|
+|| COMMAND_OPTION | Description
|
|
|
|
+*------------------------+----------------------------------------------------+
|
|
|
|
+| -threshold <threshold> | Percentage of disk capacity. This overwrites the
|
|
|
|
+| | default threshold.
|
|
|
|
+*------------------------+----------------------------------------------------+
|
|
|
|
+| -policy <policy> | <<<datanode>>> (default): Cluster is balanced if
|
|
|
|
+| | each datanode is balanced. \
|
|
|
|
+| | <<<blockpool>>>: Cluster is balanced if each block
|
|
|
|
+| | pool in each datanode is balanced.
|
|
|
|
+*------------------------+----------------------------------------------------+
|
|
|
|
+
|
|
|
|
+ Note that the <<<blockpool>>> policy is more strict than the <<<datanode>>>
|
|
|
|
+ policy.
|
|
|
|
+
|
|
|
|
+** <<<datanode>>>
|
|
|
|
+
|
|
|
|
+ Runs a HDFS datanode.
|
|
|
|
+
|
|
|
|
+ Usage: <<<hdfs datanode [-regular | -rollback | -rollingupgrace rollback]>>>
|
|
|
|
+
|
|
|
|
+*-----------------+-----------------------------------------------------------+
|
|
|
|
+|| COMMAND_OPTION || Description
|
|
|
|
+*-----------------+-----------------------------------------------------------+
|
|
|
|
+| -regular | Normal datanode startup (default).
|
|
|
|
+*-----------------+-----------------------------------------------------------+
|
|
|
|
+| -rollback | Rollsback the datanode to the previous version. This should
|
|
|
|
+| | be used after stopping the datanode and distributing the
|
|
|
|
+| | old hadoop version.
|
|
|
|
+*-----------------+-----------------------------------------------------------+
|
|
|
|
+| -rollingupgrade rollback | Rollsback a rolling upgrade operation.
|
|
|
|
+*-----------------+-----------------------------------------------------------+
|
|
|
|
+
|
|
|
|
+** <<<dfsadmin>>>
|
|
|
|
+
|
|
|
|
+ Runs a HDFS dfsadmin client.
|
|
|
|
+
|
|
|
|
+ Usage: <<<hdfs dfsadmin [GENERIC_OPTIONS]
|
|
|
|
+ [-report [-live] [-dead] [-decommissioning]]
|
|
|
|
+ [-safemode enter | leave | get | wait]
|
|
|
|
+ [-saveNamespace]
|
|
|
|
+ [-rollEdits]
|
|
|
|
+ [-restoreFailedStorage true|false|check]
|
|
|
|
+ [-refreshNodes]
|
|
|
|
+ [-setQuota <quota> <dirname>...<dirname>]
|
|
|
|
+ [-clrQuota <dirname>...<dirname>]
|
|
|
|
+ [-setSpaceQuota <quota> <dirname>...<dirname>]
|
|
|
|
+ [-clrSpaceQuota <dirname>...<dirname>]
|
|
|
|
+ [-finalizeUpgrade]
|
|
|
|
+ [-rollingUpgrade [<query>|<prepare>|<finalize>]]
|
|
|
|
+ [-metasave filename]
|
|
|
|
+ [-refreshServiceAcl]
|
|
|
|
+ [-refreshUserToGroupsMappings]
|
|
|
|
+ [-refreshSuperUserGroupsConfiguration]
|
|
|
|
+ [-refreshCallQueue]
|
|
|
|
+ [-refresh <host:ipc_port> <key> [arg1..argn]]
|
|
|
|
+ [-printTopology]
|
|
|
|
+ [-refreshNamenodes datanodehost:port]
|
|
|
|
+ [-deleteBlockPool datanode-host:port blockpoolId [force]]
|
|
|
|
+ [-setBalancerBandwidth <bandwidth in bytes per second>]
|
|
|
|
+ [-allowSnapshot <snapshotDir>]
|
|
|
|
+ [-disallowSnapshot <snapshotDir>]
|
|
|
|
+ [-fetchImage <local directory>]
|
|
|
|
+ [-shutdownDatanode <datanode_host:ipc_port> [upgrade]]
|
|
|
|
+ [-getDatanodeInfo <datanode_host:ipc_port>]
|
|
|
|
+ [-help [cmd]]>>>
|
|
|
|
+
|
|
|
|
+*-----------------+-----------------------------------------------------------+
|
|
|
|
+|| COMMAND_OPTION || Description
|
|
|
|
+*-----------------+-----------------------------------------------------------+
|
|
|
|
+| -report [-live] [-dead] [-decommissioning] | Reports basic filesystem
|
|
|
|
+ | information and statistics. Optional flags may be used to
|
|
|
|
+ | filter the list of displayed DataNodes.
|
|
|
|
+*-----------------+-----------------------------------------------------------+
|
|
|
|
+| -safemode enter\|leave\|get\|wait | Safe mode maintenance command. Safe
|
|
|
|
+ | mode is a Namenode state in which it \
|
|
|
|
+ | 1. does not accept changes to the name space (read-only) \
|
|
|
|
+ | 2. does not replicate or delete blocks. \
|
|
|
|
+ | Safe mode is entered automatically at Namenode startup, and
|
|
|
|
+ | leaves safe mode automatically when the configured minimum
|
|
|
|
+ | percentage of blocks satisfies the minimum replication
|
|
|
|
+ | condition. Safe mode can also be entered manually, but then
|
|
|
|
+ | it can only be turned off manually as well.
|
|
|
|
+*-----------------+-----------------------------------------------------------+
|
|
|
|
+| -saveNamespace | Save current namespace into storage directories and reset
|
|
|
|
+ | edits log. Requires safe mode.
|
|
|
|
+*-----------------+-----------------------------------------------------------+
|
|
|
|
+| -rollEdits | Rolls the edit log on the active NameNode.
|
|
|
|
+*-----------------+-----------------------------------------------------------+
|
|
|
|
+| -restoreFailedStorage true\|false\|check | This option will turn on/off
|
|
|
|
+ | automatic attempt to restore failed storage replicas.
|
|
|
|
+ | If a failed storage becomes available again the system will
|
|
|
|
+ | attempt to restore edits and/or fsimage during checkpoint.
|
|
|
|
+ | 'check' option will return current setting.
|
|
|
|
+*-----------------+-----------------------------------------------------------+
|
|
|
|
+| -refreshNodes | Re-read the hosts and exclude files to update the set of
|
|
|
|
+ | Datanodes that are allowed to connect to the Namenode and
|
|
|
|
+ | those that should be decommissioned or recommissioned.
|
|
|
|
+*-----------------+-----------------------------------------------------------+
|
|
|
|
+| -setQuota \<quota\> \<dirname\>...\<dirname\> | See
|
|
|
|
+ | {{{../hadoop-hdfs/HdfsQuotaAdminGuide.html#Administrative_Commands}HDFS Quotas Guide}}
|
|
|
|
+ | for the detail.
|
|
|
|
+*-----------------+-----------------------------------------------------------+
|
|
|
|
+| -clrQuota \<dirname\>...\<dirname\> | See
|
|
|
|
+ | {{{../hadoop-hdfs/HdfsQuotaAdminGuide.html#Administrative_Commands}HDFS Quotas Guide}}
|
|
|
|
+ | for the detail.
|
|
|
|
+*-----------------+-----------------------------------------------------------+
|
|
|
|
+| -setSpaceQuota \<quota\> \<dirname\>...\<dirname\> | See
|
|
|
|
+ | {{{../hadoop-hdfs/HdfsQuotaAdminGuide.html#Administrative_Commands}HDFS Quotas Guide}}
|
|
|
|
+ | for the detail.
|
|
|
|
+*-----------------+-----------------------------------------------------------+
|
|
|
|
+| -clrSpaceQuota \<dirname\>...\<dirname\> | See
|
|
|
|
+ | {{{../hadoop-hdfs/HdfsQuotaAdminGuide.html#Administrative_Commands}HDFS Quotas Guide}}
|
|
|
|
+ | for the detail.
|
|
|
|
+*-----------------+-----------------------------------------------------------+
|
|
|
|
+| -finalizeUpgrade| Finalize upgrade of HDFS. Datanodes delete their previous
|
|
|
|
+ | version working directories, followed by Namenode doing the
|
|
|
|
+ | same. This completes the upgrade process.
|
|
|
|
+*-----------------+-----------------------------------------------------------+
|
|
|
|
+| -rollingUpgrade [\<query\>\|\<prepare\>\|\<finalize\>] | See
|
|
|
|
+ | {{{../hadoop-hdfs/HdfsRollingUpgrade.html#dfsadmin_-rollingUpgrade}Rolling Upgrade document}}
|
|
|
|
+ | for the detail.
|
|
|
|
+*-----------------+-----------------------------------------------------------+
|
|
|
|
+| -metasave filename | Save Namenode's primary data structures to <filename> in
|
|
|
|
+ | the directory specified by hadoop.log.dir property.
|
|
|
|
+ | <filename> is overwritten if it exists.
|
|
|
|
+ | <filename> will contain one line for each of the following\
|
|
|
|
+ | 1. Datanodes heart beating with Namenode\
|
|
|
|
+ | 2. Blocks waiting to be replicated\
|
|
|
|
+ | 3. Blocks currrently being replicated\
|
|
|
|
+ | 4. Blocks waiting to be deleted
|
|
|
|
+*-----------------+-----------------------------------------------------------+
|
|
|
|
+| -refreshServiceAcl | Reload the service-level authorization policy file.
|
|
|
|
+*-----------------+-----------------------------------------------------------+
|
|
|
|
+| -refreshUserToGroupsMappings | Refresh user-to-groups mappings.
|
|
|
|
+*-----------------+-----------------------------------------------------------+
|
|
|
|
+| -refreshSuperUserGroupsConfiguration |Refresh superuser proxy groups mappings
|
|
|
|
+*-----------------+-----------------------------------------------------------+
|
|
|
|
+| -refreshCallQueue | Reload the call queue from config.
|
|
|
|
+*-----------------+-----------------------------------------------------------+
|
|
|
|
+| -refresh \<host:ipc_port\> \<key\> [arg1..argn] | Triggers a runtime-refresh
|
|
|
|
+ | of the resource specified by \<key\> on \<host:ipc_port\>.
|
|
|
|
+ | All other args after are sent to the host.
|
|
|
|
+*-----------------+-----------------------------------------------------------+
|
|
|
|
+| -printTopology | Print a tree of the racks and their nodes as reported by
|
|
|
|
+ | the Namenode
|
|
|
|
+*-----------------+-----------------------------------------------------------+
|
|
|
|
+| -refreshNamenodes datanodehost:port | For the given datanode, reloads the
|
|
|
|
+ | configuration files, stops serving the removed block-pools
|
|
|
|
+ | and starts serving new block-pools.
|
|
|
|
+*-----------------+-----------------------------------------------------------+
|
|
|
|
+| -deleteBlockPool datanode-host:port blockpoolId [force] | If force is passed,
|
|
|
|
+ | block pool directory for the given blockpool id on the
|
|
|
|
+ | given datanode is deleted along with its contents,
|
|
|
|
+ | otherwise the directory is deleted only if it is empty.
|
|
|
|
+ | The command will fail if datanode is still serving the
|
|
|
|
+ | block pool. Refer to refreshNamenodes to shutdown a block
|
|
|
|
+ | pool service on a datanode.
|
|
|
|
+*-----------------+-----------------------------------------------------------+
|
|
|
|
+| -setBalancerBandwidth \<bandwidth in bytes per second\> | Changes the network
|
|
|
|
+ | bandwidth used by each datanode during HDFS block
|
|
|
|
+ | balancing. \<bandwidth\> is the maximum number of bytes per
|
|
|
|
+ | second that will be used by each datanode. This value
|
|
|
|
+ | overrides the dfs.balance.bandwidthPerSec parameter.\
|
|
|
|
+ | NOTE: The new value is not persistent on the DataNode.
|
|
|
|
+*-----------------+-----------------------------------------------------------+
|
|
|
|
+| -allowSnapshot \<snapshotDir\> | Allowing snapshots of a directory to be
|
|
|
|
+ | created. If the operation completes successfully, the
|
|
|
|
+ | directory becomes snapshottable.
|
|
|
|
+*-----------------+-----------------------------------------------------------+
|
|
|
|
+| -disallowSnapshot \<snapshotDir\> | Disallowing snapshots of a directory to
|
|
|
|
+ | be created. All snapshots of the directory must be deleted
|
|
|
|
+ | before disallowing snapshots.
|
|
|
|
+*-----------------+-----------------------------------------------------------+
|
|
|
|
+| -fetchImage \<local directory\> | Downloads the most recent fsimage from the
|
|
|
|
+ | NameNode and saves it in the specified local directory.
|
|
|
|
+*-----------------+-----------------------------------------------------------+
|
|
|
|
+| -shutdownDatanode \<datanode_host:ipc_port\> [upgrade] | Submit a shutdown
|
|
|
|
+ | request for the given datanode. See
|
|
|
|
+ | {{{./HdfsRollingUpgrade.html#dfsadmin_-shutdownDatanode}Rolling Upgrade document}}
|
|
|
|
+ | for the detail.
|
|
|
|
+*-----------------+-----------------------------------------------------------+
|
|
|
|
+| -getDatanodeInfo \<datanode_host:ipc_port\> | Get the information about the
|
|
|
|
+ | given datanode. See
|
|
|
|
+ | {{{./HdfsRollingUpgrade.html#dfsadmin_-getDatanodeInfo}Rolling Upgrade document}}
|
|
|
|
+ | for the detail.
|
|
|
|
+*-----------------+-----------------------------------------------------------+
|
|
|
|
+| -help [cmd] | Displays help for the given command or all commands if none
|
|
|
|
+ | is specified.
|
|
|
|
+*-----------------+-----------------------------------------------------------+
|
|
|
|
+
|
|
|
|
+** <<<namenode>>>
|
|
|
|
+
|
|
|
|
+ Runs the namenode. More info about the upgrade, rollback and finalize is at
|
|
|
|
+ {{{./HdfsUserGuide.html#Upgrade_and_Rollback}Upgrade Rollback}}.
|
|
|
|
+
|
|
|
|
+ Usage: <<<hdfs namenode [-backup] |
|
|
|
|
+ [-checkpoint] |
|
|
|
|
+ [-format [-clusterid cid ] [-force] [-nonInteractive] ] |
|
|
|
|
+ [-upgrade [-clusterid cid] [-renameReserved<k-v pairs>] ] |
|
|
|
|
+ [-upgradeOnly [-clusterid cid] [-renameReserved<k-v pairs>] ] |
|
|
|
|
+ [-rollback] |
|
|
|
|
+ [-rollingUpgrade <downgrade|rollback> ] |
|
|
|
|
+ [-finalize] |
|
|
|
|
+ [-importCheckpoint] |
|
|
|
|
+ [-initializeSharedEdits] |
|
|
|
|
+ [-bootstrapStandby] |
|
|
|
|
+ [-recover [-force] ] |
|
|
|
|
+ [-metadataVersion ]>>>
|
|
|
|
+
|
|
|
|
+*--------------------+--------------------------------------------------------+
|
|
|
|
+|| COMMAND_OPTION || Description
|
|
|
|
+*--------------------+--------------------------------------------------------+
|
|
|
|
+| -backup | Start backup node.
|
|
|
|
+*--------------------+--------------------------------------------------------+
|
|
|
|
+| -checkpoint | Start checkpoint node.
|
|
|
|
+*--------------------+--------------------------------------------------------+
|
|
|
|
+| -format [-clusterid cid] [-force] [-nonInteractive] | Formats the specified
|
|
|
|
+ | NameNode. It starts the NameNode, formats it and then
|
|
|
|
+ | shut it down. -force option formats if the name
|
|
|
|
+ | directory exists. -nonInteractive option aborts if the
|
|
|
|
+ | name directory exists, unless -force option is specified.
|
|
|
|
+*--------------------+--------------------------------------------------------+
|
|
|
|
+| -upgrade [-clusterid cid] [-renameReserved\<k-v pairs\>] | Namenode should be
|
|
|
|
+ | started with upgrade option after
|
|
|
|
+ | the distribution of new Hadoop version.
|
|
|
|
+*--------------------+--------------------------------------------------------+
|
|
|
|
+| -upgradeOnly [-clusterid cid] [-renameReserved\<k-v pairs\>] | Upgrade the
|
|
|
|
+ | specified NameNode and then shutdown it.
|
|
|
|
+*--------------------+--------------------------------------------------------+
|
|
|
|
+| -rollback | Rollsback the NameNode to the previous version. This
|
|
|
|
+ | should be used after stopping the cluster and
|
|
|
|
+ | distributing the old Hadoop version.
|
|
|
|
+*--------------------+--------------------------------------------------------+
|
|
|
|
+| -rollingUpgrade \<downgrade\|rollback\|started\> | See
|
|
|
|
+ | {{{./HdfsRollingUpgrade.html#NameNode_Startup_Options}Rolling Upgrade document}}
|
|
|
|
+ | for the detail.
|
|
|
|
+*--------------------+--------------------------------------------------------+
|
|
|
|
+| -finalize | Finalize will remove the previous state of the files
|
|
|
|
+ | system. Recent upgrade will become permanent. Rollback
|
|
|
|
+ | option will not be available anymore. After finalization
|
|
|
|
+ | it shuts the NameNode down.
|
|
|
|
+*--------------------+--------------------------------------------------------+
|
|
|
|
+| -importCheckpoint | Loads image from a checkpoint directory and save it
|
|
|
|
+ | into the current one. Checkpoint dir is read from
|
|
|
|
+ | property fs.checkpoint.dir
|
|
|
|
+*--------------------+--------------------------------------------------------+
|
|
|
|
+| -initializeSharedEdits | Format a new shared edits dir and copy in enough
|
|
|
|
+ | edit log segments so that the standby NameNode can start
|
|
|
|
+ | up.
|
|
|
|
+*--------------------+--------------------------------------------------------+
|
|
|
|
+| -bootstrapStandby | Allows the standby NameNode's storage directories to be
|
|
|
|
+ | bootstrapped by copying the latest namespace snapshot
|
|
|
|
+ | from the active NameNode. This is used when first
|
|
|
|
+ | configuring an HA cluster.
|
|
|
|
+*--------------------+--------------------------------------------------------+
|
|
|
|
+| -recover [-force] | Recover lost metadata on a corrupt filesystem. See
|
|
|
|
+ | {{{./HdfsUserGuide.html#Recovery_Mode}HDFS User Guide}}
|
|
|
|
+ | for the detail.
|
|
|
|
+*--------------------+--------------------------------------------------------+
|
|
|
|
+| -metadataVersion | Verify that configured directories exist, then print the
|
|
|
|
+ | metadata versions of the software and the image.
|
|
|
|
+*--------------------+--------------------------------------------------------+
|
|
|
|
+
|
|
|
|
+** <<<secondarynamenode>>>
|
|
|
|
+
|
|
|
|
+ Runs the HDFS secondary namenode.
|
|
|
|
+ See {{{./HdfsUserGuide.html#Secondary_NameNode}Secondary Namenode}}
|
|
|
|
+ for more info.
|
|
|
|
+
|
|
|
|
+ Usage: <<<hdfs secondarynamenode [-checkpoint [force]] | [-format] |
|
|
|
|
+ [-geteditsize]>>>
|
|
|
|
+
|
|
|
|
+*----------------------+------------------------------------------------------+
|
|
|
|
+|| COMMAND_OPTION || Description
|
|
|
|
+*----------------------+------------------------------------------------------+
|
|
|
|
+| -checkpoint [force] | Checkpoints the SecondaryNameNode if EditLog size
|
|
|
|
+ | >= fs.checkpoint.size. If <<<force>>> is used,
|
|
|
|
+ | checkpoint irrespective of EditLog size.
|
|
|
|
+*----------------------+------------------------------------------------------+
|
|
|
|
+| -format | Format the local storage during startup.
|
|
|
|
+*----------------------+------------------------------------------------------+
|
|
|
|
+| -geteditsize | Prints the number of uncheckpointed transactions on
|
|
|
|
+ | the NameNode.
|
|
|
|
+*----------------------+------------------------------------------------------+
|