Node restart method

A method for restoring from a snapshot. This method requires shutting down and starting nodes.

If restoring a single node, you must first shutdown the node. If restoring an entire cluster, you must shut down all nodes, restore the snapshot data, and then start all nodes again.

Note: Restoring from snapshots and incremental backups temporarily causes intensive CPU and I/O activity on the node being restored.

Procedure

  1. Shut down the node.
  2. Clear all files in /var/lib/cassandra/commitlog.

    This prevents the commitlog replay from putting data back, which would defeat the purpose of restoring data to a particular point in time.

  3. Delete all *.db files in <data_directory_location>/<keyspace_name></table_name> directory, but DO NOT delete the /snapshots and /backups subdirectories.

    <data_directory_location>/<keyspace_name>/<table_name>

  4. Locate the most recent snapshot folder in this directory:

    <data_directory_location>/<keyspace_name>/<table_name>/snapshots/<snapshot_name>

  5. Copy its contents into this directory:

    <data_directory_location>/<keyspace_name>/<table_name> directory.

  6. If using incremental backups, copy all contents of this directory:

    <data_directory_location>/<keyspace_name>/<table_name>/backups

  7. Paste it into this directory:

    <data_directory_location>/<keyspace_name>/<table_name>

  8. Restart the node.

    Restarting causes a temporary burst of I/O activity and consumes a large amount of CPU resources.

  9. Run nodetool repair.

    Related topics