Apache Cassandra™ 1.2

Decommissioning a data center

Properly removing a data center ensures that no information is lost.


  1. Make sure no clients are still writing to any nodes in the data center.
  2. Run a full repair with nodetool repair.

    This ensures that all data is propagated from the data center being decommissioned.

  3. Change all keyspaces so they no longer reference the data center being removed.
  4. Run nodetool decommission on every node in the data center being removed.