}

    if (rhs_cluster_name_parts.size() != 3) {
      return errors::FailedPrecondition("unexpected rhs cluster name: ",
                                        rhs_cluster_name);
    }

    if (lhs_cluster_name_parts[0] != rhs_cluster_name_parts[0] ||
        lhs_cluster_name_parts[1] != rhs_cluster_name_parts[1]) {
      return errors::FailedPrecondition(