Assignment 2: Elastic Load Balancing and Auto Scaling

Objectives of Assignment 2

In this assignment, you are going to configure Auto Scaling and Elastic Load Balancing for your Elastic Beanstalk instance. This will build on the Wordpress deployment using Elastic Beanstalk from Lab 8. These services allow you to take an application you have built and turn it into a high capacity available application: meaning users will not see any degradation in performance regardless of how many users are connected. In the case of your Wordpress site, you will not have a high number of users trying to access it at any given time. However, the concepts of auto scaling and load balancing are part of what has lead to the popularity of the cloud. Load balancing can also be done (on premises) using things like a hardware load balancer or by installing and configuring a service such as HA Proxy (on a unique server).

AWS auto scaling requires some configuration options, such as:

• Metric: Metric used for your Auto Scaling trigger.
• Statistic: Statistic calculation the trigger should use, such as Average.
• Unit: Unit for the trigger metric, such as Bytes.
• Period: Specifies how frequently Amazon CloudWatch measures the metrics for your trigger.
• Breach duration: Amount of time, in minutes, a metric can be outside of the upper and lower thresholds before triggering a scaling operation.
• Upper threshold: If the metric exceeds this number for the breach duration, a scaling operation is triggered.
• Scale up increment: The number of Amazon EC2 instances to add when performing a scaling activity.
• Lower threshold: If the metric falls below this number for the breach duration, a scaling operation is triggered.
• Scale down increment: The number of Amazon EC2 instances to remove when performing a scaling activity.

Navigate to Elastic Beanstalk Console and click on your Environment (Wordpress-env).

1. In the navigation pane (left side), choose Configuration.
2. Scroll down to Instance traffic and scaling, and click Edit.
3. Under Capacity > Auto Scaling Group select Load balanced from the Environment type dropdown.
4. Under Instances set the following:
   • Min: 1
   • Max: 2
5. In the Scaling triggers section, configure the following settings:
   • Metric: RequestCount
   • Unit: Count
   • Period: 2 Min
   • Breach duration: 1 Min
   • Upper threshold: 5
   • Scale up increment: 1
   • Lower threshold: 1
   • Scale down increment: -1
6. Under Load balancer subnets, make sure ONLY the following are checked:

Availability Zone	Name
us-east-1a	Public Subnet 1
us-east-1b	Public Subnet 2

To save the changes choose Apply at the bottom of the page. It will take a few minutes for Elastic Beanstalk to update the environment.

Navigate to your Wordpress main page by clicking on the link provided in the Elastic Beanstalk Environment Overview.

Login to My.Custom.Domain. Repeat the steps from lab 4 to add a record, with the following information:

• Name: a2
• Type: CNAME Record
• Value: Your elastic beanstalk application URL ie wordpress-env.eba-pehkxxfr.us-east-1.elasticbeanstalk.com
• Course: OPS345
• Description: CNAME record for Elastic Beanstalk Wordpress Application

Try navigating to a2.username.mystudentproject.ca where username is your username. You should see your wordpress site. You may need to wait a few minutes for the CNAME record to propagate. You can use the Google Admin ToolBox to verify it is working.

Blog Posts:

Add a blog post detailing the following. You may need to do a little light research.

• What is Load Balancing?
• What is Horizontal Scaling aka Scaling Out?
• What is Vertical Scaling aka Scaling Up?
• What is Auto Scaling?

Add a second blog post detailing the following:

• What did you think of this assignment?
• What was the most difficult part for you?
• What was the easiest part for you?
• How did you find this course?
• What would you change about this course?

Submission

Submit screenshots showing:

• The two instances created via Auto Scaling in EC2 (navigate to EC2 > Instances)
• Your blog posts
• Your CNAME record

Rubric

Task	Mark
Two instances in EC2	8
Wordpress showing domain name	6
First Blog Post	3
Second Blog Post	3
Total	20