Web-Startup Architecture with Amazon EC2, Elastic Load Balancer, Auto-Scaling, and DynamoDB
Question
A web-startup runs its very successful social news application on Amazon EC2 with an Elastic Load Balancer, an Auto-Scaling group of Java/Tomcat application-servers, and DynamoDB as a data store.
The main web application best runs on m2 x large instances since it is highly memory-bound.
Each new deployment requires semi-automated creation and testing of a new AMI for the application servers which takes quite a while and is therefore only done once per week.
Recently, a new chat feature has been implemented in node.js and waits to be integrated into the architecture.
Answers
Explanations
Click on the arrows to vote for the correct answer
A. B. C. D.Answer - B.
You can just have one Opswork stack and multiple layers, one for Node.js and the other for the standard application.
An AWS OpsWorks Stack defines the configuration of your entire application: the load balancers, server software, database, etc.
You control every part of the stack by building layers that define the software packages deployed to your instances and other configuration details such as Elastic IPs and security groups.
You can also deploy your software onto layers by identifying the repository and optionally using Chef Recipes to automate everything Chef can do, such as creating directories and users, configuring databases, etc.
You can use OpsWorks Stacks' built-in automation to scale your application and automatically recover from instance failures.
You can control who can view and manage the resources used by your application, including ssh access to the instances that your application uses.
For more information on Ops work, please visit the below URL.
https://aws.amazon.com/opsworks/stacks/faqs/The correct answer to this question is B. Create one AWS Ops Works stack, create two AWS Ops Works layers and create one custom recipe.
Explanation: OpsWorks is a configuration management service provided by AWS. It helps to automate the deployment, configuration, and management of applications across an infrastructure.
In this scenario, a new chat feature has been implemented in node.js and needs to be integrated into the existing architecture. To integrate this new feature, the following steps can be taken:
Create an AWS OpsWorks stack: A stack is a container for AWS resources that are created and managed together as a single unit. In this case, we can create an AWS OpsWorks stack to manage the infrastructure for the application.
Create two AWS OpsWorks layers: A layer is a blueprint for instances in a stack. We can create two AWS OpsWorks layers - one for the Java/Tomcat application servers and another for the new node.js chat feature.
Create one custom recipe: A recipe is a set of instructions that tell OpsWorks how to configure instances in a layer. We can create a custom recipe for the new node.js chat feature that can be applied to instances in the layer.
Using this approach, we can ensure that the existing Java/Tomcat application servers continue to run on m2 x large instances while the new node.js chat feature runs on instances that are better suited for running node.js. Additionally, we can also automate the deployment and configuration of the new feature using OpsWorks, making it easier to integrate with the existing infrastructure.
Option A is incorrect because it suggests creating only one AWS OpsWorks layer which wouldn't be sufficient to manage the infrastructure for the Java/Tomcat application servers and the new node.js chat feature.
Option C is incorrect because it suggests creating two separate AWS OpsWorks stacks which would unnecessarily complicate the management of the infrastructure.
Option D is incorrect because it suggests creating two custom recipes which is not required as the new node.js chat feature can be managed with just one custom recipe.
