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Clean the HBase Master procedure store

HBase Master procedures changed after HBase 2.1, therefore the procedure store must be cleaned before upgrading from CDH 6 to CDP.

From HBase 2.2 it is changed how HBase Master performs internal, housekeeping operations such as table creation or region removal. As a result if a procedure is started in HBase 2.1 (CDH 6 version), it cannot be continued after upgrading to HBase 2.2 (CDP version).

To prevent such cases you must clean the HMase Master procedure store before starting the upgrade and you can find this functionality from Cloudera Manager 7.7.1 and above.

  1. In Cloudera Manager, select the HBase service.
  2. Click Actions > Cleanup Master Procedures Before Upgrade
    HBase Master rules are stopped and restarted in a so-called upgrade mode. In this mode HBase Masters are waiting for all ongoing procedures to finish. Once an HBase Master procedure store is empty, its HBase Master quits automatically.
  3. Optional: If the cleanup command fails, check if there are any stuck procedures that need to be cleaned manually before upgrade.
    If the command fails, the following error message is displayed: Failed to prepare HBase for the upgrade. There might be some HBase Master procedures which haven’t been finished in time. Please make sure you clean these procedures before you would continue the upgrade.

    For more information, see Using the HBCK2 tool to remediate HBase clusters.

  4. Start the upgrade.
  5. Find the Other Tasks section of the Upgrade Wizard.
  6. Check the Yes, I have run the "Cleanup master procedure before upgrade" action, it finished successfully and I haven't started HBase Master since then.
Continue the upgrade using the Cloudera Manager upgrade wizard.