eks-vpc.yaml

---
AWSTemplateFormatVersion: '2010-09-09'
Description: 'VPC, Subnets, InternetGateway has Created'

Parameters:

  VpcBlock:
    Type: String
    Default: 10.0.0.0/16
    Description: The CIDR range for the VPC. This should be a valid private (RFC 1918) CIDR range.

  Subnet01Block:
    Type: String
    Default: 10.0.1.0/24
    Description: CidrBlock for subnet 01 within the VPC

  Subnet02Block:
    Type: String
    Default: 10.0.2.0/24
    Description: CidrBlock for subnet 02 within the VPC

  Subnet03Block:
    Type: String
    Default: 10.0.3.0/24
    Description: CidrBlock for subnet 03 within the VPC. This is used only if the region has more than 2 AZs.

Metadata:
  AWS::CloudFormation::Interface:
    ParameterGroups:
      -
        Label:
          default: "Worker Network Configuration"
        Parameters:
          - VpcBlock
          - Subnet01Block
          - Subnet02Block
          - Subnet03Block

Conditions:
  Has2Azs:
    Fn::Or:
      - Fn::Equals:
        - {Ref: 'AWS::Region'}
        - us-east-2a
      - Fn::Equals:
        - {Ref: 'AWS::Region'}
        - us-east-2b
      - Fn::Equals:
        - {Ref: 'AWS::Region'}
        - us-east-2c

  HasMoreThan2Azs:
    Fn::Not:
      - Condition: Has2Azs

Resources:
  VPC:
    Type: AWS::EC2::VPC
    Properties:
      CidrBlock:  !Ref VpcBlock
      EnableDnsSupport: true
      EnableDnsHostnames: true
      Tags:
      - Key: Name
        Value: !Sub '${AWS::StackName}-VPC'

  InternetGateway:
    Type: "AWS::EC2::InternetGateway"

  VPCGatewayAttachment:
    Type: "AWS::EC2::VPCGatewayAttachment"
    Properties:
      InternetGatewayId: !Ref InternetGateway
      VpcId: !Ref VPC

  RouteTable:
    Type: AWS::EC2::RouteTable
    Properties:
      VpcId: !Ref VPC
      Tags:
      - Key: Name
        Value: Public Subnets
      - Key: Network
        Value: Public

  Route:
    DependsOn: VPCGatewayAttachment
    Type: AWS::EC2::Route
    Properties:
      RouteTableId: !Ref RouteTable
      DestinationCidrBlock: 0.0.0.0/0
      GatewayId: !Ref InternetGateway

  Subnet01:
    Type: AWS::EC2::Subnet
    Metadata:
      Comment: Subnet 01
    Properties:
      AvailabilityZone:
        Fn::Select:
        - '0'
        - Fn::GetAZs:
            Ref: AWS::Region
      CidrBlock:
        Ref: Subnet01Block
      VpcId:
        Ref: VPC
      Tags:
      - Key: Name
        Value: !Sub "${AWS::StackName}-Subnet01"

  Subnet02:
    Type: AWS::EC2::Subnet
    Metadata:
      Comment: Subnet 02
    Properties:
      AvailabilityZone:
        Fn::Select:
        - '1'
        - Fn::GetAZs:
            Ref: AWS::Region
      CidrBlock:
        Ref: Subnet02Block
      VpcId:
        Ref: VPC
      Tags:
      - Key: Name
        Value: !Sub "${AWS::StackName}-Subnet02"

  Subnet03:
    Condition: HasMoreThan2Azs
    Type: AWS::EC2::Subnet
    Metadata:
      Comment: Subnet 03
    Properties:
      AvailabilityZone:
        Fn::Select:
        - '2'
        - Fn::GetAZs:
            Ref: AWS::Region
      CidrBlock:
        Ref: Subnet03Block
      VpcId:
        Ref: VPC
      Tags:
      - Key: Name
        Value: !Sub "${AWS::StackName}-Subnet03"

  Subnet01RouteTableAssociation:
    Type: AWS::EC2::SubnetRouteTableAssociation
    Properties:
      SubnetId: !Ref Subnet01
      RouteTableId: !Ref RouteTable

  Subnet02RouteTableAssociation:
    Type: AWS::EC2::SubnetRouteTableAssociation
    Properties:
      SubnetId: !Ref Subnet02
      RouteTableId: !Ref RouteTable

  Subnet03RouteTableAssociation:
    Condition: HasMoreThan2Azs
    Type: AWS::EC2::SubnetRouteTableAssociation
    Properties:
      SubnetId: !Ref Subnet03
      RouteTableId: !Ref RouteTable

  ControlPlaneSecurityGroup:
    Type: AWS::EC2::SecurityGroup
    Properties:
      GroupDescription: Cluster communication with worker nodes
      VpcId: !Ref VPC

Outputs:

  SubnetIds:
    Description: All subnets in the VPC
    Value:
      Fn::If:
      - HasMoreThan2Azs
      - !Join [ ",", [ !Ref Subnet01, !Ref Subnet02, !Ref Subnet03 ] ]
      - !Join [ ",", [ !Ref Subnet01, !Ref Subnet02 ] ]

  SecurityGroups:
    Description: Security group for the cluster control plane communication with worker nodes
    Value: !Join [ ",", [ !Ref ControlPlaneSecurityGroup ] ]

  VpcId:
    Description: The VPC Id
    Value: !Ref VPC