amazon-web-services - AWS CloudFormation RDS 实例无法创建 - 找不到 DBCluster

Question

我正在使用 cloudformation，并遇到了无法解决的 DBSubnetGroup 问题。我的目标是构建一个简单的设置:

• 具有两个子网的 VPC
• 这些子网上的 RDS 数据库子网组
• 该数据库子网中的 RDS 数据库集群
• 该集群中的单个 RDS 实例

在cloudformation中，我不断收到错误:

Could not find DB Cluster: MyRDSClusterId (Service: AmazonRDS; Status Code: 
404; Error Code: DBClusterNotFoundFault; Request ID: ...)

在我看来，一切都正确，cloudformation 表示我的 DBCluster 已正确创建。我在这里做错了什么？任何对我做错的事情的见解将不胜感激。

这是我的云信息模板:

AWSTemplateFormatVersion: "2010-09-09"
Description: Stack with DBSubnetGroup, DBCluster, and one DBInstance
Resources:
  MyAppVPC:
    Type: AWS::EC2::VPC
    Properties:
      CidrBlock: 192.168.0.0/16
      EnableDnsSupport: true
      EnableDnsHostnames: true
      InstanceTenancy: default
  MyAppRDSSubnetA:
    Type: AWS::EC2::Subnet
    Properties:
      AvailabilityZone: us-east-1a
      VpcId: !Ref MyAppVPC
      CidrBlock: 192.168.0.0/24
      MapPublicIpOnLaunch: true
  MyAppRDSSubnetB:
    Type: AWS::EC2::Subnet
    Properties:
      AvailabilityZone: us-east-1b
      VpcId: !Ref MyAppVPC
      CidrBlock: 192.168.1.0/24
      MapPublicIpOnLaunch: true
  MyDBSubnetGroup:
    Type: AWS::RDS::DBSubnetGroup
    Properties:
      DBSubnetGroupDescription: My App DBSubnetGroup for RDS
      SubnetIds:
        - !Ref MyAppRDSSubnetA
        - !Ref MyAppRDSSubnetB
  MyRDSCluster:
    Type: AWS::RDS::DBCluster
    Properties:
      BackupRetentionPeriod: 1
      DatabaseName: MyDB
      DBClusterIdentifier: MyRDSClusterId
      DBSubnetGroupName: !Ref MyDBSubnetGroup
      Engine: aurora
      MasterUsername: exampleUsername
      MasterUserPassword: examplePassword
  MyRDSInstance:
    Type: AWS::RDS::DBInstance
    Properties:
      DBClusterIdentifier: !Ref MyRDSCluster
      DBInstanceClass: db.t2.small
      DBSubnetGroupName: !Ref MyDBSubnetGroup
      Engine: aurora      

Answer 1

DBClusterIdentifier 名称中的某些字符为大写。cloudformation 的作用是，它自动将所有大写字符转换为小写。现在，当您尝试在 DBCluster 下附加 DBInstances 时，无法使用您提到的 DBClusterIdentifier 找到它，因为它包含一些大写字母。

MyRDSCluster:
    Type: AWS::RDS::DBCluster
    Properties:
      BackupRetentionPeriod: 1
      DatabaseName: MyDB
      DBClusterIdentifier: MyRDSClusterId <- here it converts all string to lowercase
      DBSubnetGroupName: !Ref MyDBSubnetGroup
      Engine: aurora
      MasterUsername: exampleUsername
      MasterUserPassword: examplePassword
  MyRDSInstance:
    Type: AWS::RDS::DBInstance
    Properties:
      DBClusterIdentifier: !Ref MyRDSCluster <- here it does not, so mismatch in name
      DBInstanceClass: db.t2.small
      DBSubnetGroupName: !Ref MyDBSubnetGroup
      Engine: aurora

解决方案是:将 DBClusterIdentifier 全部小写。

我希望您能得到答案:)