EC2-Load balancer

{
  "AWSTemplateFormatVersion": "2010-09-09",
  "Description": "AWS Cloud Formation template to launch an EC2 Instance and 
                  a LoadBalancer",
  "Parameters": {
  "AvailabilityZone": {
      "Description": "select the Availability Zone to launch the Instance",
      "Type": "AWS::EC2::AvailabilityZone::Name"
    },
  "EC2InstanceType": {
      "Description": "Type of EC2 instance to launch.",
      "Type": "String",
      "Default": "t2.micro",
      "AllowedValues" : [
        "cc2.8xlarge",
        "c3.8xlarge",
        "c3.4xlarge",
        "c3.2xlarge",
        "c3.xlarge",
        "c3.large",
        "c4.8xlarge",
        "c4.4xlarge",
        "c4.2xlarge",
        "c4.xlarge",
        "c4.large",
        "r3.8xlarge",
        "r3.4xlarge",
        "r3.2xlarge",
        "r3.xlarge",
        "r3.large",
        "i2.8xlarge",
        "i2.4xlarge",
        "i2.2xlarge",
        "i2.xlarge",
        "cr1.8xlarge",
        "cg1.4xlarge",
        "m3.medium",
        "m3.large",
        "m3.xlarge",
        "m3.2xlarge",
        "hi1.4xlarge",
        "g2.2xlarge",
        "t2.micro",
        "t2.small",
        "t2.medium",
        "t2.large",
        "t2.nano",
        "d2.8xlarge",
        "d2.4xlarge",
        "d2.2xlarge",
        "d2.xlarge",
        "m4.large",
        "m4.xlarge",
        "m4.2xlarge",
        "m4.4xlarge",
        "m4.10xlarge"
      ],
      "ConstraintDescription": "must be a valid EC2 instance type."
    },
  "KeyPair" : {
    "Description" : "Amazon EC2 Key Pair",
    "Type" : "AWS::EC2::KeyPair::KeyName"
  },
  "EC2InstanceAMI": {
      "Description": "Type the Instance AMI ID",
      "Default": "ami-8fcee4e5",
      "Type": "String"
    },
  "SubnetID": {
      "Description": "Choose the SubnetID to attach with the EC2 Instance",
      "Type": "AWS::EC2::Subnet::Id"
    },
  "SecurityGroupID": {
      "Description": "Select the Security Group for EC2 Instance",
      "Type": "AWS::EC2::SecurityGroup::Id"
    }
},
"Resources":{
  "Ec2Instance" : {
      "Type" : "AWS::EC2::Instance",
      "Properties" : {
        "AvailabilityZone": {"Ref": "AvailabilityZone"},
        "InstanceType": {"Ref": "EC2InstanceType"},
        "SubnetId": {"Ref": "SubnetID"},
        "SecurityGroupIds" : [ { "Ref" : "SecurityGroupID" }],
        "ImageId": {"Ref": "EC2InstanceAMI"},
        "KeyName": {"Ref": "KeyPair"},
        "Tags": [
          {
            "Key": "Name",
            "Value": "Instance-01"
          }
        ]
      }
    },
  "ElasticLoadBalancer" : {
      "Type" : "AWS::ElasticLoadBalancing::LoadBalancer",
      "Properties" : {
        "Instances" : [ { "Ref" : "Ec2Instance" } ],
        "Subnets": [{"Ref": "SubnetID"}],
        "CrossZone" : true,
        "SecurityGroups" : [ { "Ref" : "SecurityGroupID" }],
        "LoadBalancerName" : "ELB-01",
        "Tags" :[
          {
            "Key": "Name",
            "Value": "ELB-01"
          }
        ],
        "Listeners": [{
          "LoadBalancerPort": "80",
          "InstancePort": "80",
          "Protocol": "HTTP"
        }],
        "HealthCheck": {
          "Target": "HTTP:80/",
          "HealthyThreshold": "3",
          "UnhealthyThreshold": "5",
          "Interval": "30",
          "Timeout": "5"
        },
        "ConnectionDrainingPolicy": {
          "Enabled" : "true",
          "Timeout" : "60"
        }
      }
    }
  },
  "Outputs": {
    "EC2InstanceID":{
      "Value" : {"Ref": "Ec2Instance"},
      "Description" : "The Instance ID of the created Ec2 Instance"
    },
    "ELBDNS":{
      "Value" : { "Fn::GetAtt" : ["ElasticLoadBalancer", "DNSName"] },
      "Description" : "The Public DNS of the created ELB"
    }
  }
}