![\"AWS](\"https://s3.amazonaws.com/cloudformation-examples/cloudformation_graphic.png\")
",
"This is a multi-tier web application launched in an Amazon Virtual Private Cloud (Amazon VPC) with multiple subnets. The first subnet is public and contains and internet facing load balancer, a NAT device for internet access from the private subnet and a bastion host to allow SSH access to the hosts in the private subnet. The second subnet is private and contains a Frontend fleet of EC2 instances, an internal load balancer and a Backend fleet of EC2 instances.", "
To serve a web page from the backend service, click here.
" ]]}, "mode" : "000644", "owner" : "root", "group" : "root" }, "/etc/httpd/conf.d/maptobackend.conf" : { "content" : { "Fn::Join" : ["", [ "ProxyPass /backend http://", { "Fn::GetAtt" : [ "PrivateElasticLoadBalancer", "DNSName" ]}, "\n", "ProxyPassReverse /backend http://", { "Fn::GetAtt" : [ "PrivateElasticLoadBalancer", "DNSName" ]}, "\n" ]]}, "mode" : "000644", "owner" : "root", "group" : "root" } }, "services" : { "sysvinit" : { "httpd" : { "enabled" : "true", "ensureRunning" : "true", "files" : [ "/etc/httpd/conf.d/maptobackend.conf", "/var/www/html/index.html" ] } } } } } }, "Properties" : { "ImageId" : { "Fn::FindInMap" : [ "AWSRegionArch2AMI", { "Ref" : "AWS::Region" }, { "Fn::FindInMap" : [ "AWSInstanceType2Arch", { "Ref" : "FrontendInstanceType" }, "Arch" ] } ] }, "SecurityGroups" : [ { "Ref" : "FrontendSecurityGroup" } ], "InstanceType" : { "Ref" : "FrontendInstanceType" }, "KeyName" : { "Ref" : "KeyName" }, "UserData" : { "Fn::Base64" : { "Fn::Join" : ["", [ "#!/bin/bash -v\n", "yum update -y aws-cfn-bootstrap\n", "# Install Apache and configure as a reverse Frontend\n", "/opt/aws/bin/cfn-init --stack ", { "Ref" : "AWS::StackId" }, " --resource FrontendServerLaunchConfig ", " --region ", { "Ref" : "AWS::Region" }, "\n", "# Signal completion\n", "/opt/aws/bin/cfn-signal -e $? -r \"Frontend setup done\" '", { "Ref" : "FrontendWaitHandle" }, "'\n" ]]}} } }, "FrontendSecurityGroup" : { "Type" : "AWS::EC2::SecurityGroup", "Properties" : { "GroupDescription" : "Allow access from load balancer and bastion as well as outbound HTTP and HTTPS traffic", "VpcId" : { "Ref" : "VPC" }, "SecurityGroupIngress" : [ { "IpProtocol" : "tcp", "FromPort" : "80", "ToPort" : "80", "SourceSecurityGroupId" : { "Ref" : "PublicLoadBalancerSecurityGroup" } } , { "IpProtocol" : "tcp", "FromPort" : "22", "ToPort" : "22", "SourceSecurityGroupId" : { "Ref" : "BastionSecurityGroup" } } ], "SecurityGroupEgress" : [ { "IpProtocol" : "tcp", "FromPort" : "80", "ToPort" : "80", "CidrIp" : "0.0.0.0/0" } , { "IpProtocol" : "tcp", "FromPort" : "443", "ToPort" : "443", "CidrIp" : "0.0.0.0/0" } ] } }, "FrontendWaitHandle" : { "Type" : "AWS::CloudFormation::WaitConditionHandle" }, "FrontendWaitCondition" : { "Type" : "AWS::CloudFormation::WaitCondition", "DependsOn" : "FrontendFleet", "Properties" : { "Handle" : { "Ref" : "FrontendWaitHandle" }, "Timeout" : "300", "Count" : { "Ref" : "FrontendSize" } } }, "PrivateElasticLoadBalancer" : { "Type" : "AWS::ElasticLoadBalancing::LoadBalancer", "Properties" : { "SecurityGroups" : [ { "Ref" : "PrivateLoadBalancerSecurityGroup" } ], "Subnets" : [ { "Ref" : "PrivateSubnet" } ], "Listeners" : [ { "LoadBalancerPort" : "80", "InstancePort" : "80", "Protocol" : "HTTP" } ], "Scheme" : "internal", "HealthCheck" : { "Target" : "HTTP:80/", "HealthyThreshold" : "3", "UnhealthyThreshold" : "5", "Interval" : "90", "Timeout" : "60" } } }, "PrivateLoadBalancerSecurityGroup" : { "Type" : "AWS::EC2::SecurityGroup", "Properties" : { "GroupDescription" : "Private ELB Security Group with HTTP access on port 80 from the Frontend Fleet only", "VpcId" : { "Ref" : "VPC" }, "SecurityGroupIngress" : [ { "IpProtocol" : "tcp", "FromPort" : "80", "ToPort" : "80", "SourceSecurityGroupId" : { "Ref" : "FrontendSecurityGroup" } } ], "SecurityGroupEgress" : [ { "IpProtocol" : "tcp", "FromPort" : "80", "ToPort" : "80", "CidrIp" : "0.0.0.0/0" } ] } }, "BackendFleet" : { "Type" : "AWS::AutoScaling::AutoScalingGroup", "Properties" : { "AvailabilityZones" : [{ "Fn::GetAtt" : [ "PrivateSubnet", "AvailabilityZone" ] }], "VPCZoneIdentifier" : [{ "Ref" : "PrivateSubnet" }], "LaunchConfigurationName" : { "Ref" : "BackendLaunchConfig" }, "MinSize" : "1", "MaxSize" : "10", "DesiredCapacity" : { "Ref" : "BackendSize" }, "LoadBalancerNames" : [ { "Ref" : "PrivateElasticLoadBalancer" } ], "Tags" : [ { "Key" : "Network", "Value" : "Private", "PropagateAtLaunch" : "true" } ] } }, "BackendLaunchConfig" : { "Type" : "AWS::AutoScaling::LaunchConfiguration", "Metadata" : { "Comment1" : "Configure the Backend server to respond to requests", "AWS::CloudFormation::Init" : { "config" : { "packages" : { "yum" : { "httpd" : [] } }, "files" : { "/var/www/html/index.html" : { "content" : { "Fn::Join" : ["\n", [ "",
"