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上一篇，我们对Hadoop命令进行了简略的列举，但是Hadoop命令特多，还有一部分没有列举完，官网基本都是英文的，所以只能拙略的翻译下，妄大家见谅。
下面，我们就开始对Hadoop命令中进行讲解。
一：介绍
所有的HDFS命令通过bin/ HDFS脚本调用。指定参数运行HDFS脚本会打印所有命令的描述。
用法: hdfs [SHELL_OPTIONS] COMMAND [GENERIC_OPTIONS] [COMMAND_OPTIONS]
Hadoop有一个选项解析框架用于解析一般的选项和运行类。
COMMAND_OPTIONS Description --config
--loglevelThe common set of shell options. These are documented on the Commands Manual page. GENERIC_OPTIONS The common set of options supported by multiple commands. See the Hadoop Commands Manual for more information. COMMAND COMMAND_OPTIONS Various commands with their options are described in the following sections. The commands have been grouped into User Commands and Administration Commands.
一：介绍
用于Hadoop集群用户命令。
二：classPath
打印Hadoop jar和需要的库类路径。
用法: hdfs classpath
三：dfs
运行在支持Hadoop文件系统文件系统的命令.The various COMMAND_OPTIONS can be found at File System Shell Guide.
用法: hdfs dfs [COMMAND [COMMAND_OPTIONS]]
四：fetchdt
从NameNode获取授权令牌.See fetchdt for more info.
用法: hdfs fetchdt [--webservice <namenode_http_addr>] <path>
五：fsck
在HDFS文件系统检查工具.See fsck for more info.
用法：hdfs fsck <path>
[-list-corruptfileblocks |
[-move | -delete | -openforwrite]
[-files [-blocks [-locations | -racks]]]
[-includeSnapshots]六：getconf
从配置目录中获取配置信息然后处理。
用法：hdfs getconf -namenodes
hdfs getconf -secondaryNameNodes
hdfs getconf -backupNodes
hdfs getconf -includeFile
hdfs getconf -excludeFile
hdfs getconf -nnRpcAddresses
hdfs getconf -confKey [key]七：groups
返回给定的一个或多个用户组信息。
用法: hdfs groups [username ...]
八：lsSnapshottableDir
获得snapshottable目录列表。当是超级用户运行时，它返回所有的snapshottable目录。否则它返回当前用户所拥有的目录。
用法: hdfs lsSnapshottableDir [-help]
九：jmxget
把一个服务的JMX信息丢弃
用法: hdfs jmxget [-localVM ConnectorURL | -port port | -server mbeanserver | -service service]
十：oev
Hadoop离线编辑查看器。
用法: hdfs oev [OPTIONS] -i INPUT_FILE -o OUTPUT_FILE
十一：oiv
用于查看较新的镜像文件的Hadoop离线镜像查看器
用法: hdfs oiv [OPTIONS] -i INPUT_FILE
十二：oiv_legacy
老版本的Hadoop Hadoop离线镜像查看器。
用法: hdfs oiv_legacy [OPTIONS] -i INPUT_FILE -o OUTPUT_FILE
十三：snapshotDiff
确定HDFS的快照之间的差异。See the HDFS Snapshot Documentation for more information.
用法: hdfs snapshotDiff <path> <fromSnapshot> <toSnapshot>
十四：version
打印版本。
用法: hdfs version
一：介绍
用于Hadoop集群用户命令。
二：balancer
运行群集平衡实用程序。管理员可以按Ctrl-C停止再平衡过程。See Balancer for more details.
用法：hdfs balancer
[-threshold <threshold>]
[-policy <policy>]
[-exclude [-f <hosts-file> | <comma-separated list of hosts>]]
[-include [-f <hosts-file> | <comma-separated list of hosts>]]
[-idleiterations <idleiterations>]三：crypto
See the HDFS Transparent Encryption Documentation for more information.
用法：hdfs crypto -createZone -keyName <keyName> -path <path>
hdfs crypto -help <command-name>
hdfs crypto -listZones四：datanode
运行一个HDFS datanode
用法: hdfs datanode [-regular | -rollback | -rollingupgrace rollback]
五：dfsadmin
运行一个HDFS dfsadmin客户端
用法：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>]
[-setStoragePolicy <path> <policyName>]
[-getStoragePolicy <path>]
[-finalizeUpgrade]
[-rollingUpgrade [<query> |<prepare> |<finalize>]]
[-metasave filename]
[-refreshServiceAcl]
[-refreshUserToGroupsMappings]
[-refreshSuperUserGroupsConfiguration]
[-refreshCallQueue]
[-refresh <host:ipc_port> <key> [arg1..argn]]
[-reconfig <datanode |...> <host:ipc_port> <start |status>]
[-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>]
[-triggerBlockReport [-incremental] <datanode_host:ipc_port>]
[-help [cmd]]六：haadmin
See HDFS HA with NFS or HDFS HA with QJM for more information on this command.
用法：hdfs haadmin -checkHealth <serviceId>
hdfs haadmin -failover [--forcefence] [--forceactive] <serviceId> <serviceId>
hdfs haadmin -getServiceState <serviceId>
hdfs haadmin -help <command>
hdfs haadmin -transitionToActive <serviceId> [--forceactive]
hdfs haadmin -transitionToStandby <serviceId>七：journalnode
This comamnd starts a journalnode for use with HDFS HA with QJM.
用法: hdfs journalnode
八：mover
运行数据迁移实用程序. See Mover for more details.
用法: hdfs mover [-p <files/dirs> | -f <local file name>]
九：namenode
运行namenode. More info about the upgrade, rollback and finalize is at Upgrade Rollback.
用法：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 ]十：nfs3
该指令从HDFS nfs3服务使用nfs3网关。
用法: hdfs nfs3
十一：portmap
该指令从HDFS nfs3服务使用RPC portmap。
用法：Usage: hdfs portmap
十二：secondarynamenode
运行 second namenode.See Secondary Namenode for more info.
用法: hdfs secondarynamenode [-checkpoint [force]] | [-format] | [-geteditsize]
十三：storagepolicies
列出所有存储策。See the HDFS Storage Policy Documentation for more information.
十四：zkfc
这个指令开始一个管理员切换控制器的过程使用HDFS HA QJM。
用法: hdfs zkfc [-formatZK [-force] [-nonInteractive]]
一：介绍
为了帮助管理员调试HDFS问题有用的命令，如验证块文件和调用recoverlease。
二：verify
HDFS的元数据和文件块的验证。如果一个块指定文件，我们将验证在元数据文件的校验和匹配块文件。
用法: hdfs debug verify [-meta <metadata-file>] [-block <block-file>]
三：recoverLease
恢复指定路径上的租约。路径必须驻留在一个HDFS文件系统。重试的默认号码是1。
用法: hdfs debug recoverLease [-path <path>] [-retries <num-retries>]
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到此，本章节的内容讲述完毕。
Apache hadoop commands:http://hadoop.apache.org/docs/current/hadoop-project-dist/hadoop-hdfs/HDFSCommands.html
Apache 1.04 中文：http://hadoop.apache.org/docs/r1.0.4/cn/commands_manual.html
【源】从零自学Hadoop系列索引
本文版权归mephisto和博客园共有，欢迎转载，但须保留此段声明，并给出原文链接，谢谢合作。
文章是哥(mephisto)写的，SourceLink