AWS Practices

VPC/Subnet/Internet Gateway (1 instance)

1_1_vpc_1_public_subnet_1_instance_1_internet_gateway.json: Simple stack that contains one VPC, one public subnet, Internet gateway and one instance connected to the internet through the gateway.

VPC/Subnet/Internet Gateway (2 instances)

2_1_vpc_1_public_subnet_2_instances_1_internet_gateway.json: Simple stack that contains one VPC, one public subnet, Internet gateway and two instances connected to the internet through the gateway.

The above sample has been updated to:

• Include one more instance in the same public subnet but without assigning a publicIP.
• Add IpProtocol icmp from port 8 to all -1 in SecurityGroup to enable ping request between the machines.

VPC/2 Subnets/Internet Gateway (2 instances)

3_1_vpc_1_public_subnet_1_private_subnet_2_instances_1_internet_gateway.json: Simple stack that contains one VPC, one public subnet, one private subnet, Internet gateway and two instances. The public subnet connected to the internet through the CustomRouteTable route the traffic to the Internet gateway. The private subnet is not connected to the internet and use the MainRouteTable.

The above sample has been updated to:

• Move the private instance to a private subnet.

VPC/Subnet/Internet Gateway with recovery alarm (1 instance)

4_1_vpc_1_public_subnet_1_instance_1_internet_gateway_recovery_alarm.json: Same as VPC/Subnet/Internet Gateway (1 instance) but a recovery alarm CloudWatch was added. UserData added to start jenkins server on 8080 for later use

VPC/2 Subnets/Internet Gateway/AutoScaling (1 instance max/min)

5_1_vpc_2_public_subnet_1_internet_gateway_autoscaling.json: Simple stack that contains one VPC, two public subnets, Internet gateway, launch configruation and autoscaling for one instance min/max two instances. The subnets connected to the internet through the CustomRouteTable route the traffic to the Internet gateway.

VPC/2 Subnets/Internet Gateway/AutoScaling/EBS Recovery (1 instance max/min)

6_1_vpc_2_public_subnet_1_internet_gateway_autoscaling_ebs_recovery.json: Same as VPC/2 Subnets/Internet Gateway/AutoScaling (1 instance max/min) but the imageId is parameterized as an optional parameter. so we can:

• Create snapshots of the EBS volume, and use snapshot if a virtual server needs to recover in another availability zone. EBS snapshots are stored on S3 to be available in multiple availability zones.

aws ec2 create-image --instance-id=i-0ad5005528a7ed71f --name jenkins-instance

wait until recieving available for the image status.

aws ec2 describe-images --image-id $newImageId --query "Images[].State"

• Update the stack with the new imageId.

aws cloudformation update-stack --stack-name $stackName --template-url $tempateUrl --parameters ParameterKey=JenkinsAdminPassword,UsePreviousValue=true ParameterKey=AMISnapshot,ParameterValue=$newImageId

To Test it:

• Open the jenkins server and create a job (just to make sure that the EBS Recovery is working)
• Write down the current instance avaialability zone.
• Terminiate the current running instance

aws ec2 terminate-instances --instance-ids $instanceId

• Wait until the instance terminiated and newely instance created.
• Get the new publicIP
• Log in to the jenkins server http://$publicIP:8080/ and verify if the job is there.

To clean up:

Run below:

aws cloudformation delete-stack --stack-name $stackName
aws cloudformation describe-stacks --stack-name $stackName #wait until return error or stack deleted.
aws ec2 deregister-image --image-id $newImageId
aws ec2 delete-snapshot --snapshot-id $snapshotId

VPC/2 Subnets/Internet Gateway/AutoScaling/EBS Recovery/ElasticIP (1 instance max/min)

7_1_vpc_2_public_subnet_1_internet_gateway_autoscaling_ebs_recovery_elastic_ip.json: Same as VPC/2 Subnets/Internet Gateway/AutoScaling/EBS Recovery (1 instance max/min) but overcoming the problem of assigning another publicIP/PrivateIP to the new instance in another availability zone since we can't keep the same publicIP between different zones. By default, you also can’t use an Elastic IP as a public IP address for a virtual server launched by auto-scaling.

• Allocating an Elastic IP
• Adding the association of an Elastic IP to the script in the user data
• Creating an IAM role and policy to allow the EC2 instance to associate an Elastic IP

To Test it:

• Open the jenkins server with the elasticIP assigned.
• Terminiate the current running instance
• Wait until the instance terminiated and newely instance created.
• Log in to the jenkins server http://$elasticIP:8080/ and verify if jenkins is running.

VPC/2 Subnets/Internet Gateway/AutoScaling/EBS Recovery/LoadBalaner (2 instance max/min)

8_1_vpc_2_public_subnet_1_internet_gateway_autoscaling_ebs_recovery_loadbalancer.json: Same as VPC/2 Subnets/Internet Gateway/AutoScaling/EBS Recovery (1 instance max/min) but overcoming the problem of assigning another publicIP/PrivateIP to the new instance in another availability zone since we can't keep the same publicIP between different zones. For that reason, a loadbalancer has been created to distribute the traffic to the EC2 instances. Once a new instance created, It registers itself to the loadbalaner.

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• draw.io source folder.