How To Migrate Load Balanced Application by Using a Blue Green and Canary Deployment Strategy

Step 1. Create resources by using cloudformation template

• Click Next

• Click Next

• Click Submit

• Wait until Create_Complete

Step 2. Configure the blue deployment

• Click Target Groups

• Click Blue

• Click Register targets

• Select Blue EC2 and Click Include as pending below

• Click Register pending targets

• Wait Health status as Healthy

• Click Load Balancer

• Click BlueGreenALB

• Click 1 rule

• Check that the Forward to value is Blue: 100 (100%).

• Click BlueGreenALB

• Copy DNS and paste in new tab

Step 3. Configure the green deployment

• Click Target Groups

• Click Green

• Click Register targets

• Choose Green EC2

• Click Register pending targets

• Click Load Balancer

• Click BlueGreenALB

• Select HTTP:80 and Click Manage rules and Edit rules

• Select Default and Click Actions and Edit rule

• Click Add target group

• Choose Green and Update Weight and Click Save change

• Click Refresh Icon

• Click BlueGreenALB

• Copy DNS and paste in new tab

• If stable, change weight to 50% and test DNS again

Step 4. Change route all traffic to the Green target group by using a CloudFormation change set

• In the AWS Management console, on the navigation bar, type and select the CloudFormation service.

• Select Blue-Green-and-Canary-Deployment and click Stack actions and Create change set for current stack

• Choose Edit in Application Composer and Click Edit in Application Composer

• Click Go to Desinger

• Select and delete the BlueWebServer1 and BlueWebServer2 resources.

• In the BlueGreenALBListener resource, in TargetGroupArn, change the value to !Ref GreenTargetGroup.

• Delete BlueTargetGroup

• Click Refresh, Validate and Save Icon

• Select Replace existing template and Click Next

• Write RemoveBlueEC2andTargetGroup and Click Next

• Click Next

• Click Submit

• Check In the Changes section,the change will remove the BlueTargetGroup, BlueWebServer1, and BlueWebServer2 resources, and modify the BlueGreenALBListener.

• Click Execute change set

• Click Execute change set and Wait until Update_Complete

• Click Load Balancer

• Click BlueGreenALB

• Copy DNS and paste in new tab

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