Set up a storage policy for HDFS
You can use Cloudera Manager to set up storage policy on a DataNode data directory.
Check the HDFS Service Advanced Configuration Snippet (Safety Valve)
for hdfs-site.xml to be sure that
dfs.storage.policy.enabledhas not been changed from its default value of
Specify the storage types for each DataNode Data Directory that is not a
standard disk, by adding the storage type in brackets at the beginning of the
[SSD]/dfs/dn1 [DISK]/dfs/dn2 [ARCHIVE]/dfs/dn3
Open a terminal session on any HDFS host and run the hdfs
storagepolicies -setStoragePolicy command for each path on which
you want to set a storage policy.
hdfs storagepolicies -setStoragePolicy -path <path> -policy <policy> path_to_file_or_directory -policy policy_name
To move the data to the appropriate storage based on the current storage
policy, use the mover utility, from any HDFS host.
Use mover -h to get a list of available options. To migrate all data at once (this may take a long time), you can set the path to
hdfs mover -p <path>