AWS CloudFormation: Target Group for Application Load Balancer is not working for multiple EC2 instances

Estou a enviar a minha infra-estrutura para a AWS usando o modelo de formação de nuvens. A minha infra-estrutura tem um balancer de carga de aplicação que aponta para um grupo-alvo. O grupo-alvo terá múltiplas instâncias EC2.

o seguinte é o meu grupo-alvo e as instâncias EC2 no modelo.

Resources:
  PublicSubnet1:
    Type: AWS::EC2::Subnet
    Properties:
      VpcId: !Ref Vpc
      CidrBlock: !Select [ 0, !Cidr [ !Ref VpcCidr, 12, 8 ] ]
      MapPublicIpOnLaunch: True
      AvailabilityZone: !Select
        - 0
        - Fn::GetAZs: !Ref AWS::Region
  PublicSubnet2:
    Type: AWS::EC2::Subnet
    Properties:
      VpcId: !Ref Vpc
      CidrBlock: !Select [ 1, !Cidr [ !Ref VpcCidr, 12, 8 ] ]
      MapPublicIpOnLaunch: True
      AvailabilityZone: !Select
        - 1
        - Fn::GetAZs: !Ref AWS::Region
  PublicSubnet3:
    Type: AWS::EC2::Subnet
    Properties:
      VpcId: !Ref Vpc
      CidrBlock: !Select [ 2, !Cidr [ !Ref VpcCidr, 12, 8 ] ]
      MapPublicIpOnLaunch: True
      AvailabilityZone: !Select
        - 2
        - Fn::GetAZs: !Ref AWS::Region
  InternetGateway:
    Type: AWS::EC2::InternetGateway
  AttachGateway:
    Type: AWS::EC2::VPCGatewayAttachment
    Properties:
      VpcId: !Ref Vpc
      InternetGatewayId: !Ref InternetGateway
  RouteTable:
    Type: AWS::EC2::RouteTable
    Properties:
      VpcId: !Ref Vpc
  Route:
    Type: AWS::EC2::Route
    DependsOn: InternetGateway
    Properties:
      RouteTableId: !Ref RouteTable
      DestinationCidrBlock: 0.0.0.0/0
      GatewayId: !Ref InternetGateway
  SubnetRouteTableAssociation:
    Type: AWS::EC2::SubnetRouteTableAssociation
    Properties:
      SubnetId: !Ref PublicSubnet1
      RouteTableId: !Ref RouteTable
  LoadBalancerSecurityGroup:
    Type: AWS::EC2::SecurityGroup
    Properties:
      GroupDescription: Application Load Balancer Security Group
      SecurityGroupIngress:
        - IpProtocol: tcp
          FromPort: '80'
          ToPort: '80'
          CidrIp: 0.0.0.0/0
        - IpProtocol: tcp
          FromPort: '443'
          ToPort: '443'
          CidrIp: 0.0.0.0/0
      VpcId: !Ref Vpc
  LoadBalancer:
    Type: AWS::ElasticLoadBalancingV2::LoadBalancer
    Properties:
      Name: ApplicationLoadBalancer
      Subnets:
        - !Ref PublicSubnet1
        - !Ref PublicSubnet2
        - !Ref PublicSubnet3
      SecurityGroups:
        - !Ref LoadBalancerSecurityGroup
  LoadBalancerListener:
    Type: AWS::ElasticLoadBalancingV2::Listener
    Properties:
      LoadBalancerArn: !Ref LoadBalancer
      Port: 80
      Protocol: HTTP
      DefaultActions:
        - Type: forward
          TargetGroupArn: !Ref ApplicationTargetGroup
  ApplicationTargetGroup:
    Type: AWS::ElasticLoadBalancingV2::TargetGroup
    Properties:
      HealthCheckIntervalSeconds: 30
      HealthCheckProtocol: HTTP
      HealthCheckTimeoutSeconds: 15
      HealthyThresholdCount: 5
      UnhealthyThresholdCount: 3
      Matcher:
        HttpCode: '200'
      Name: ApplicationTargetGroup
      VpcId: !Ref Vpc
      Port: 80
      Protocol: HTTP
      TargetGroupAttributes:
        - Key: deregistration_delay.timeout_seconds
          Value: '20'
      Targets:
        - Id: !Ref WebServerInstance1
          Port: 80
        - Id: !Ref WebServerInstance2
            Port: 80
  WebServerInstance1:
    Type: AWS::EC2::Instance
    Properties:
      InstanceType: !Ref InstanceType
      KeyName: !Ref KeyName
      SubnetId: !Ref PublicSubnet1
      SecurityGroupIds:
        - !Ref WebServerSecurityGroup
      ImageId:
        Fn::FindInMap:
          - AWSRegionArch2AMI
          - Ref: AWS::Region
          - Fn::FindInMap:
              - AWSInstanceType2Arch
              - Ref: InstanceType
              - Arch
      AvailabilityZone: !Select
        - 0
        - Fn::GetAZs: !Ref AWS::Region
      UserData:
        Fn::Base64: !Sub |
          #!/bin/bash -xe
          cd /tmp
          yum update -y
          yum install -y httpd24
          echo "Welcome from the instance 1" > /var/www/html/index.html
          sudo -u root service httpd start
  WebServerInstance2:
    Type: AWS::EC2::Instance
    Properties:
      InstanceType: !Ref InstanceType
      KeyName: !Ref KeyName
      SubnetId: !Ref PublicSubnet1
      SecurityGroupIds:
        - !Ref WebServerSecurityGroup
      ImageId:
        Fn::FindInMap:
          - AWSRegionArch2AMI
          - Ref: AWS::Region
          - Fn::FindInMap:
              - AWSInstanceType2Arch
              - Ref: InstanceType
              - Arch
      AvailabilityZone: !Select
        - 0
        - Fn::GetAZs: !Ref AWS::Region
      UserData:
        Fn::Base64: !Sub |
          #!/bin/bash -xe
          cd /tmp
          yum update -y
          yum install -y httpd24
          echo "Welcome from the instance 2" > /var/www/html/index.html
          sudo -u root service httpd start
  WebServerSecurityGroup:
    Type: AWS::EC2::SecurityGroup
    Properties:
      GroupDescription: Enable HTTP access via port 80
      SecurityGroupIngress:
        - IpProtocol: tcp
          FromPort: '80'
          ToPort: '80'
          CidrIp: 0.0.0.0/0
        - IpProtocol: tcp
          FromPort: '22'
          ToPort: '22'
          CidrIp:
            Ref: SSHLocation
      VpcId: !Ref Vpc
Como podem ver, o meu grupo alvo tem dois alvos. Mas quando eu implantei e abri o balancer de carga DNS no navegador, ele apenas continua carregando, carregando e carregamento. Mas se atribuo apenas uma instância EC2 ao grupo-alvo, está a funcionar como esperado. Não está a funcionar para várias instâncias. O que há de errado com o meu modelo e como posso corrigi-lo?

Author: Wai Yan Hein, 2020-07-27
Source

1 answers

Posso confirmar que a causa da rota é que apenas uma das sub-redes públicas tem uma associação de tabela de rotas para uma tabela de rotas com um portal de internet. Adicione uma associação de sub-redes para cada sub-rede e ela deve desaparecer. {[[2]} isto é porque o tráfego não podia ser encaminhado para as sub-redes que não tinham a Associação para que a ligação pendurada.

Abaixo está o modelo de trabalho 

Resources:
  PublicSubnet1:
    Type: AWS::EC2::Subnet
    Properties:
      VpcId: !Ref Vpc
      CidrBlock: !Select [ 0, !Cidr [ !Ref VpcCidr, 12, 8 ] ]
      MapPublicIpOnLaunch: True
      AvailabilityZone: !Select
        - 0
        - Fn::GetAZs: !Ref AWS::Region
  PublicSubnet2:
    Type: AWS::EC2::Subnet
    Properties:
      VpcId: !Ref Vpc
      CidrBlock: !Select [ 1, !Cidr [ !Ref VpcCidr, 12, 8 ] ]
      MapPublicIpOnLaunch: True
      AvailabilityZone: !Select
        - 1
        - Fn::GetAZs: !Ref AWS::Region
  PublicSubnet3:
    Type: AWS::EC2::Subnet
    Properties:
      VpcId: !Ref Vpc
      CidrBlock: !Select [ 2, !Cidr [ !Ref VpcCidr, 12, 8 ] ]
      MapPublicIpOnLaunch: True
      AvailabilityZone: !Select
        - 2
        - Fn::GetAZs: !Ref AWS::Region
  InternetGateway:
    Type: AWS::EC2::InternetGateway
  AttachGateway:
    Type: AWS::EC2::VPCGatewayAttachment
    Properties:
      VpcId: !Ref Vpc
      InternetGatewayId: !Ref InternetGateway
  RouteTable:
    Type: AWS::EC2::RouteTable
    Properties:
      VpcId: !Ref Vpc
  Route:
    Type: AWS::EC2::Route
    DependsOn: InternetGateway
    Properties:
      RouteTableId: !Ref RouteTable
      DestinationCidrBlock: 0.0.0.0/0
      GatewayId: !Ref InternetGateway
  SubnetRouteTableAssociation:
    Type: AWS::EC2::SubnetRouteTableAssociation
    Properties:
      SubnetId: !Ref PublicSubnet1
      RouteTableId: !Ref RouteTable
  SubnetRouteTableAssociationB:
    Type: AWS::EC2::SubnetRouteTableAssociation
    Properties:
      SubnetId: !Ref PublicSubnet2
      RouteTableId: !Ref RouteTable
  SubnetRouteTableAssociationC:
    Type: AWS::EC2::SubnetRouteTableAssociation
    Properties:
      SubnetId: !Ref PublicSubnet3
      RouteTableId: !Ref RouteTable
  LoadBalancerSecurityGroup:
    Type: AWS::EC2::SecurityGroup
    Properties:
      GroupDescription: Application Load Balancer Security Group
      SecurityGroupIngress:
        - IpProtocol: tcp
          FromPort: '80'
          ToPort: '80'
          CidrIp: 0.0.0.0/0
        - IpProtocol: tcp
          FromPort: '443'
          ToPort: '443'
          CidrIp: 0.0.0.0/0
      VpcId: !Ref Vpc
  LoadBalancer:
    Type: AWS::ElasticLoadBalancingV2::LoadBalancer
    Properties:
      Name: ApplicationLoadBalancer
      Subnets:
        - !Ref PublicSubnet1
        - !Ref PublicSubnet2
        - !Ref PublicSubnet3
      SecurityGroups:
        - !Ref LoadBalancerSecurityGroup
  LoadBalancerListener:
    Type: AWS::ElasticLoadBalancingV2::Listener
    Properties:
      LoadBalancerArn: !Ref LoadBalancer
      Port: 80
      Protocol: HTTP
      DefaultActions:
        - Type: forward
          TargetGroupArn: !Ref ApplicationTargetGroup
  ApplicationTargetGroup:
    Type: AWS::ElasticLoadBalancingV2::TargetGroup
    Properties:
      HealthCheckIntervalSeconds: 30
      HealthCheckProtocol: HTTP
      HealthCheckTimeoutSeconds: 15
      HealthyThresholdCount: 5
      UnhealthyThresholdCount: 3
      Matcher:
        HttpCode: '200'
      Name: ApplicationTargetGroup
      VpcId: !Ref Vpc
      Port: 80
      Protocol: HTTP
      TargetGroupAttributes:
        - Key: deregistration_delay.timeout_seconds
          Value: '20'
      Targets:
        - Id: !Ref WebServerInstance1
          Port: 80
        - Id: !Ref WebServerInstance2
          Port: 80
  WebServerInstance1:
    Type: AWS::EC2::Instance
    Properties:
      InstanceType: !Ref InstanceType
      KeyName: !Ref KeyName
      SubnetId: !Ref PublicSubnet1
      SecurityGroupIds:
        - !Ref WebServerSecurityGroup
      ImageId:
        Fn::FindInMap:
          - AWSRegionArch2AMI
          - Ref: AWS::Region
          - Fn::FindInMap:
              - AWSInstanceType2Arch
              - Ref: InstanceType
              - Arch
      AvailabilityZone: !Select
        - 0
        - Fn::GetAZs: !Ref AWS::Region
      UserData:
        Fn::Base64: !Sub |
          #!/bin/bash -xe
          cd /tmp
          yum update -y
          yum install -y httpd24
          echo "Welcome from the instance 1" > /var/www/html/index.html
          sudo -u root service httpd start
  WebServerInstance2:
    Type: AWS::EC2::Instance
    Properties:
      InstanceType: !Ref InstanceType
      KeyName: !Ref KeyName
      SubnetId: !Ref PublicSubnet1
      SecurityGroupIds:
        - !Ref WebServerSecurityGroup
      ImageId:
        Fn::FindInMap:
          - AWSRegionArch2AMI
          - Ref: AWS::Region
          - Fn::FindInMap:
              - AWSInstanceType2Arch
              - Ref: InstanceType
              - Arch
      AvailabilityZone: !Select
        - 0
        - Fn::GetAZs: !Ref AWS::Region
      UserData:
        Fn::Base64: !Sub |
          #!/bin/bash -xe
          cd /tmp
          yum update -y
          yum install -y httpd24
          echo "Welcome from the instance 2" > /var/www/html/index.html
          sudo -u root service httpd start
  WebServerSecurityGroup:
    Type: AWS::EC2::SecurityGroup
    Properties:
      GroupDescription: Enable HTTP access via port 80
      SecurityGroupIngress:
        - IpProtocol: tcp
          FromPort: '80'
          ToPort: '80'
          CidrIp: 0.0.0.0/0
        - IpProtocol: tcp
          FromPort: '22'
          ToPort: '22'
          CidrIp:
            Ref: SSHLocation
      VpcId: !Ref Vpc
```
 2
Author: Chris Williams, 2020-07-27 17:40:59