Table of Contents

About

Snapshots support storing a copy of data at a particular instant of time. One usage of the snapshot feature may be to roll back a corrupted HDFS instance to a previously known good point in time.

Management

See HDFS - Fs Shell

Allow

See HDFS - DFSAdmin option -allowSnapshot

<snapshotDir>'' : Allow snapshots to be taken on a directory.
Disallow

See HDFS - DFSAdmin option -disallowSnapshot

<snapshotDir>'' : Do not allow snapshots to be taken on a directory any more.
Diff

HDFS - hdfs command line diff sub-command make a diff of two snapshots of a directory or diff the current directory contents with a snapshot 

hdfs snapshotDiff
List

list all snapshottable dirs owned by the current user 

hdfs lsSnapshottableDir
Documentation / Reference