Rehydrating HDFS files

Using Pentaho Data Storage Optimizer

Part Number

Perform the following steps to rehydrate HDFS files:

Note: Rules-governed rehydration is only available for tiered HDFS files.
  1. Click Management. 
    The Manage Your Environment page opens.
  2. On the Rules card, click Add New > Add Rule Definition.
    The Rule Definition page opens.
  3. Create a rule definition. The following example uses a file size for the definition.
    1. Enter a name for the rule definition in the Name field.
      For example, Rehydrate Moved Files.
    2. Enter a description of the rule definition in the Description field.
    3. Click Select an option and choose FILE or FOLDER as the object type.
    4. Click Add Condition to create the query condition.
    5. Click Select attribute and select the attribute from the menu.
      For example, File Size.
    6. Click Operator and select an operator.
      For example, Greater than or equal to.
    7. Enter a size in the Size field.
      For example, 9.
    8. Click Unit and select the unit size from the menu.
      For example, GB.
    9. Click Add Action > Start Process.
    10. Click Select Process > Rehydrate.
    11. Click Save.
  4. On the Rules card, click Add New > Add Rule.
    The Metadata Rule page opens.
  5. Create a metadata rule. The following example uses the Rehydrate Moved Files rule definition, above.
    1. Enter a name for the rule in the Rule Name field.
      For example, Restore Tiered Files.
    2. Click Source Data Asset and select the data source on which to run the metadata rule.
    3. Click Select the rule definition and select the rule definition.
      For example, Rehydrate Moved Files.
    4. Select Run rule definition now to run the rule immediately.
    5. You can also click Add Schedule to enter a time to run it later.
  6. Click Apply.
Files marked Tiered that are greater than or equal to 9 GB are rehydrated.
To view the results, go to the Manage Your Environment page and on the Data Operations card, click Submitted. On the Data Operations page, the status of the operation, file name, path, source, type, and destination are provided.