private boolean enoughReplicas() {
    if (localReplicas.size() < localReplicaSuccessTarget) {
      logger.error("Not enough replicas in local data center for partition " + partitionId
          + " to satisfy paranoid durability requirements " + "(wanted " + localReplicaSuccessTarget + ", but found " + localReplicas.size() + ")");
      routerMetrics.paranoidDurabilityNotEnoughReplicasCount.inc();
      return false;
    }

    if (remoteReplicas.size() < remoteReplicaSuccessTarget) {
      logger.error("Not enough replicas in remote data centers for partition " + partitionId
          + " to satisfy paranoid durability requirements " + "(wanted " + remoteReplicaSuccessTarget + ", but found " + remoteReplicas.size() + ")");
      routerMetrics.paranoidDurabilityNotEnoughReplicasCount.inc();
      return false;
    }
    return true;
  }
Check if there are enough replicas to satisfy the paranoid durability requirements.
@return true if there are enough replicas, false otherwise.
ambry-router/src/main/java/com/github/ambry/router/ParanoidDurabilityOperationTracker.java