@Override
  protected void rollbackState(final MasterProcedureEnv env, final RestoreSnapshotState state)
    throws IOException {
    if (state == RestoreSnapshotState.RESTORE_SNAPSHOT_PRE_OPERATION) {
      // nothing to rollback
      return;
    }

    // The restore snapshot doesn't have a rollback. The execution will succeed, at some point.
    throw new UnsupportedOperationException("unhandled state=" + state);
  }
Set up monitor status if it is not created.
hbase-server/src/main/java/org/apache/hadoop/hbase/master/procedure/RestoreSnapshotProcedure.java