创建EMR集群出错，EMR服务角色无效

Question

我正在通过 cloudformation 和 lambda function 创建一个 emr 集群。创建堆栈后，当我运行 lambda function 时，它通过提供 EMR 服务角色来启动集群：无效错误。 附上我的服务角色和工作流程角色代码。 这是我缺少的权限，或者我应该给予的权限，以便我的 emr 开始执行这些步骤。

EMRClusterServiceRole:
    Type: 'AWS::IAM::Role'
    Properties:
      AssumeRolePolicyDocument:
        Version: 2012-10-17
        Statement:
        - Effect: Allow
          Principal:
            Service:
            - ec2.amazonaws.com
          Action:
          - 'sts:AssumeRole'
      ManagedPolicyArns:
            - arn:aws:iam::aws:policy/service-role/AmazonElasticMapReduceforEC2Role
      Path: /

  EMRClusterinstanceProfileRole: 
    Type: 'AWS::IAM::Role'
    Properties:
      AssumeRolePolicyDocument:
        Version: 2012-10-17
        Statement:
        - Effect: Allow
          Principal: 
            Service: 
            - ec2.amazonaws.com
          Action: 
          - 'sts:AssumeRole'
      ManagedPolicyArns: 
        - arn:aws:iam::aws:policy/service-role/AmazonElasticMapReduceforEC2Role
      Path: /

  EMRClusterinstanceProfile:
    Type: AWS::IAM::InstanceProfile
    Properties:
      Path: /
      Roles:
      - !Ref EMRClusterinstanceProfileRole

  EMRJobFlowProfileinstance: 
    Type: AWS::IAM::InstanceProfile
    Properties:
      Path: /
      Roles:
      - !Ref EMRJobFlowRole


  EMRJobFlowRole:       
    Type: AWS::IAM::Role
    Properties:
      AssumeRolePolicyDocument:
        Version: 2012-10-17
        Statement:
        - Effect: Allow
          Principal: 
            Service: 
            - ec2.amazonaws.com
          Action: 
          - 'sts:AssumeRole'
      ManagedPolicyArns: 
        - arn:aws:iam::aws:policy/service-role/AmazonElasticMapReduceforEC2Role
      Path: /    

Answer 1

根据评论，解决方案是使用elasticmapreduce.amazonaws.com信任策略原则。