HDFS CLI
Overview
This section includes the reference documentation for the HDFS shell CLI.
Using hdfs commands without any arguments outputs a description for all these commands.
The usage is as follows:
$ hdfs [SHELL_OPTIONS] COMMAND [GENERIC_OPTIONS] [COMMAND_OPTIONS]Hadoop has an option parsing framework that employs parsing generic options as well as running classes.
SHELL_OPTIONS |
The common set of shell options |
GENERIC_OPTIONS |
The common set of options supported by multiple commands |
COMMAND_OPTIONS |
Various commands with their options are described in the following sections |
User commands
These commands are helpful for users of a Hadoop cluster.
| Command | Description |
|---|---|
Prints the class path needed to get the Hadoop JAR and the required libraries |
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Runs a filesystem command on the file system supported in Hadoop |
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Displays computed Hadoop environment variables |
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Gets Delegation Token from a NameNode |
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Runs the HDFS filesystem checking utility |
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Gets configuration information from the configuration directory, post-processing |
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Returns the group information given one or more usernames |
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Runs HttpFS server, the HDFS HTTP Gateway |
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Gets the list of snapshot table directories |
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Dumps JMX information from a service |
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Hadoop offline edits viewer |
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Hadoop Offline Image Viewer for image files |
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Hadoop Offline Image Viewer for older versions of Hadoop |
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Determines the difference between HDFS snapshots |
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Prints the version |
Administration commands
These commands are useful for administrators of a Hadoop cluster.
| Command | Description |
|---|---|
Runs a cluster balancing utility |
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Interacts with cache pools and directives via the hdfs cacheadmin subcommand |
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Creates a new encryption zone |
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Runs an HDFS DataNode |
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Runs an HDFS dfsadmin client |
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Runs the DFS router |
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Manages Router-based federation |
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Runs the disk balancer CLI |
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Runs the ErasureCoding CLI |
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Gets access to some additional commands to administer the HA HDFS cluster |
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Starts a JournalNode for use with HDFS HA with QJM |
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Runs the data migration utility |
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Runs the NameNode |
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Starts the NFS3 gateway for use with the HDFS NFS3 Service |
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Starts the RPC portmap for use with the HDFS NFS3 Service |
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Runs the HDFS secondary NameNode |
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Lists out all/gets/sets/unsets storage policies |
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Starts a ZooKeeper Failover Controller process for use with HDFS HA with QJM |