This is the documentation for Cloudera Manager 5.0.x. Documentation for other versions is available at Cloudera Documentation.

The HBase Service

Cloudera Manager requires certain additional steps to set up and configure the HBase service.

Creating the HBase Root Directory

When adding the HBase service, the Add Service wizard automatically creates a root directory for HBase in HDFS. If you quit the Add Service wizard or it does not finish, you can create the root directory outside the wizard by doing these steps:

  1. Choose Create Root Directory from the Actions menu in the HBase > Status tab.
  2. Click Create Root Directory again to confirm.

Graceful Shutdown

A graceful shutdown of an HBase RegionServer allows the regions hosted by that RegionServer to be moved to other RegionServers before stopping the RegionServer. Cloudera Manager provides the following configuration options to perform a graceful shutdown of either an HBase RegionServer or the entire service.

Gracefully Shutting Down an HBase RegionServer

  1. Navigate to the HBase Service > Instances tab.
  2. From the list of Role Instances, select the RegionServer you want to shut down gracefully.
  3. From the Actions for Selected drop-down menu, select Decommission (Graceful Stop).
  Note: To simply shut down a RegionServer without moving regions off it, select Stop from the Actions for Selected menu. This is only recommended if graceful shutdown isn't working for some reason, since this can cause regions to become temporarily unavailable.

Gracefully Shutting Down the HBase Service

  1. Navigate to the HBase service and from the Actions menu, and select Stop... This tries to perform an HBase Master-driven graceful shutdown for the length of the configured Graceful Shutdown Timeout (three minutes by default), after which it abruptly shuts down the whole service.

Configuring the Graceful Shutdown Timeout Property

This timeout only affects a graceful shutdown of the entire HBase service, not individual RegionServers. Therefore, if you have a large cluster with many RegionServers, you should strongly consider increasing the timeout from its default of 180 seconds.

  1. Go to the HBase service.
  2. Select Configuration > View and Edit.
  3. Under the Service-Wide category, scroll down to the Graceful Shutdown Timeout property and click on the current Value to change it.
  4. Click Save Changes to save this setting.

Enabling HBase Indexing

HBase indexing is dependent on the Lily HBase Indexer service. The Lily HBase Indexer service indexes the stream of records being added to HBase tables. Indexing allows you to query data stored in HBase with the Solr service.

  1. Go to the HBase service.
  2. Select Configuration > View and Edit.
  3. Select the Backup category.
  4. Check the properties for Enable Replication and Enable Indexing, and click Save Changes.
  5. Restart the HBase service.

Configuring Short-Circuit Reads

So-called "short-circuit" reads bypass the DataNode, allowing the client to read the file directly, as long as the client is co-located with the data. Short-circuit reads provide a substantial performance boost to many applications and help improve your HBase random read profile.

  Note: Short-circuit reads are enabled by default in Cloudera Manager.
  1. Go to the HDFS service.
  2. Select Configuration > View and Edit.
  3. Type "shortcircuit" into the Search field to display the Enable HDFS Short Circuit Read property, and verify that this feature is enabled (set to True).
  4. Go to the HBase service.
  5. Select Configuration > View and Edit.
  6. Search for "shortcircuit".
  7. Verify that the Enable HDFS Short Circuit Read property is enabled.
Page generated September 3, 2015.