Amazon Web Services CLF-C02 - AWS Certified Cloud Practitioner

Decoupling the components of an application means reducing the dependencies and interactions between them, which can improve the application’s reliability, scalability, and performance. Decoupling can be achieved by using services such as Amazon Simple Queue Service (Amazon SQS), Amazon Simple Notification Service (Amazon SNS), and AWS Lambda1

Amazon Kendra is a highly accurate and easy to use intelligent search service powered by machine learning. It enables users to easily find the content they are looking for, even when it is scattered across multiple locations and content repositories within their organization. Amazon Kendra supports natural language queries, and can search fortext in documents stored in Amazon S3, as well as other sources such as SharePoint, OneDrive, Salesforce, ServiceNow, and more1.

Amazon Rekognition is a computer vision service that makes it easy to add image and video analysis to applications. It can detect objects, faces, text, scenes, activities, and emotions in images and videos. However, it is not designed for searching for text in documents stored in Amazon S32.

Amazon Polly is a text-to-speech service that turns text into lifelike speech. It can create audio versions of books, articles, podcasts, and more. However, it is not designed for searching for text in documents stored in Amazon S33.

Amazon Lex is a service for building conversational interfaces using voice and text. It can create chatbots that can interact with users using natural language. However, it is not designed for searching for text in documents stored in Amazon S34.

Using EC2 instances in a single Availability Zone is a solution that meets the requirements of minimizing network latency between the EC2 instances and not needing high availability. An Availability Zone is a physically isolated location within an AWS Region that has its own power, cooling, and network connectivity. EC2 instances within the same Availability Zone can communicate with each other using low-latency private IP addresses. However, EC2 instances in a single Availability Zone are not highly available, because they are vulnerable to failures or disruptions that affect the Availability Zone

The AWS service that will meet this requirement is C. AWS Backup.

AWS Backup is a service that allows you to define a central data protection policy that works across AWS services for compute, storage, and database resources. You can use AWS Backup to create backup plans that specify the frequency, retention, and lifecycle of your backups, and apply them to your AWS resources using tags or resource IDs.AWS Backup supports various AWS services, such as Amazon EC2,Amazon EBS, Amazon RDS, Amazon DynamoDB, Amazon EFS, Amazon FSx, and AWS Storage Gateway12.

AWS Batch is a service that allows you to run batch computing workloads on AWS.AWS Batch does not provide a central data protection policy, but rather enables you to optimize the allocation and utilization of your compute resources3.

AWS Elastic Disaster Recovery is a service that allows you to prepare for and recover from disasters using AWS.AWS Elastic Disaster Recovery does not provide a central data protection policy, but rather helps you minimize downtime and data loss by replicating your applications and data to AWS4.

Amazon FSx is a service that provides fully managed file storage for Windows and Linux applications.Amazon FSx does not provide a central data protection policy, but rather offers features such as encryption, snapshots, backups, and replication to protect your file systems5.

 AWS Pricing Calculator can be used to estimate costs before deployment. AWS Pricing Calculator is a tool that helps the user to compare the cost of AWS services for different use cases and configurations. The user can create estimates for various AWS services, such as Amazon EC2, Amazon S3, Amazon RDS, and more. The user can also adjust the parameters, such as region, instance type, storage size, and duration, to see how they affect the cost. AWS Pricing Calculator provides a detailed breakdown of the estimated cost, as well as a summary of the key drivers of the cost.

Cost optimization is the pillar of the AWS Well-Architected Framework that aligns with the requirements of not relying on elaborate forecasting and paying only for the resources that are used. The cost optimization pillar focuses on the ability of a system to deliver business value at the lowest price point. Cost optimization involves using the right AWS services and resources for the workload, measuring and monitoring the cost and usage, and continuously improving the cost efficiency. Cost optimization also leverages the benefits of the AWS Cloud, such as pay-as-you-go pricing, elasticity, and scalability. For more information, see [Cost Optimization Pillar] and [Cost Optimization].

 Amazon Relational Database Service (Amazon RDS) is a service that provides fully managed relational database engines. Amazon RDS supports several database engines, including Oracle, MySQL, PostgreSQL, MariaDB, SQL Server, and Amazon Aurora. Amazon RDS can be used to migrate an application that includes an Oracle database to AWS without rewriting the application, as long as the application is compatible with the Oracle version and edition supported by Amazon RDS. Amazon RDS can also provide benefits such as high availability, scalability, security, backup and restore, and performance optimization. [Amazon RDS Overview] AWS Certified Cloud Practitioner - aws.amazon.com

AWS Outposts is a service that offers fully managed and configurable compute and storage racks built with AWS-designed hardware that allow you to run your workloads on premises and seamlessly connect to AWS services in the cloud. AWS Outposts is ideal for workloads that require low latency, local data processing, or local data storage. With AWS Outposts, you can use the same AWS APIs, tools, and infrastructure across on premises and the cloud to deliver a truly consistent hybrid experience5. Availability Zones are isolated locations within each AWS Region that are engineered to be fault-tolerant and provide high availability. AWS Local Zones are extensions of AWS Regions that are placed closer to large population, industry, and IT centers where no AWS Region exists today. AWS Wavelength is a service that enables developers to build applications that deliver ultra-low latency to mobile devices and users by deploying AWS compute and storage at the edge of the 5G network. None of these services or features can help you host a critical application with minimum latency at a remote site that has a slow internet connection.

 Pay-as-you-go pricing is an AWS benefit that demonstrates the ability of users to replace upfront fixed expenses with variable expenses. With pay-as-you-go pricing, users only pay for the resources they consume, without any long-term contracts or commitments. This can lower the total cost of ownership and increase the return on investment. Pay-as-you-go pricing also provides flexibility and scalability, as users can adjust their resource usage according to their changing needs and demands. AWS Cloud Value FrameworkAWS Certified Cloud Practitioner - aws.amazon.com

 The correct answer is B because AWS Cloud9 is an AWS service that enables users to run their existing custom, nonproduction workloads in the AWS Cloud quickly and cost-effectively. AWS Cloud9 is a cloud-based integrated development environment (IDE) that allows users to write, run, and debug code from a web browser. AWS Cloud9 supports multiple programming languages, such as Python, Java, Node.js, and more. AWS Cloud9 also provides users with a terminal that can access AWS services and resources, such as Amazon EC2 instances, AWS Lambda functions, and AWS CloudFormation stacks. The other options are incorrect because they are not AWS services that enable users to run their existing custom, nonproduction workloads in the AWS Cloud quickly and cost-effectively. AWS CodeBuild is an AWS service that enables users to compile, test, and package their code for deployment. AWS OpsWorks is an AWS service that enables users to configure and manage their applications using Chef or Puppet. AWS Cloud Development Kit (AWS CDK) is an AWS service that enables users to define and provision their cloud infrastructure using familiar programming languages, such as TypeScript, Python, Java, and C#. Reference: AWS Cloud9 FAQs

AWS Secrets Manager is the AWS service where database credentials should be stored for maximum security. AWS Secrets Manager helps to protect the secrets, such as database credentials, passwords, API keys, and tokens, that are used to access applications, services, and resources. AWS Secrets Manager enables secure storage, encryption, rotation, and retrieval of the secrets. AWS Secrets Manager also integrates with other AWS services, such as AWS Identity and Access Management (IAM), AWS Key Management Service (AWS KMS), and AWS Lambda. For more information, see [What is AWS Secrets Manager?] and [Getting Started with AWS Secrets Manager].

Reliability is the cloud concept that this architecture represents. Reliability is the ability of a system to recover from infrastructure or service disruptions, dynamically acquire computing resources to meet demand, and mitigate disruptions such as misconfigurations or transient network issues. Deploying an application to multiple AWS Regions and configuring automatic failoverbetween those Regions enhances the reliability of the application by reducing the impact of regional failures and increasing the availability of the application4

 Cost Explorer is an AWS service or tool that can be used to forecast AWS spending. It allows users to analyze their AWS costs and usage using interactive graphs and tables. It also provides features such as filtering, grouping, and forecasting to help users plan their future spending. Amazon DevPay is an AWS service that allows developers to sell applications that are built on AWS services. It handles the billing and metering for the customers of the applications and collects payments from them. It is not a tool for forecasting AWS spending. AWS Organizations is an AWS service that allows users to centrally manage and govern their AWS accounts. It provides features such as creating groups of accounts, applying policies, and automating account creation. It is not a tool for forecasting AWS spending. AWS Trusted Advisor is an AWS service that provides best practices and recommendations to optimize the performance, security, and cost of AWS resources. It can helpusers identify opportunities to reduce their AWS costs, but it is not a tool for forecasting AWS spending

 VPC Flow Logs is the AWS service or feature that is used to troubleshoot network connectivity issues between Amazon EC2 instances. VPC Flow Logs is a feature that enables users to captureinformation about the IP traffic going to and from network interfaces in their VPC. VPC Flow Logs can help users monitor and diagnose network-related issues, such as traffic not reaching an instance, or an instance not responding to requests. VPC Flow Logs can be published to Amazon CloudWatch Logs, Amazon S3, or Amazon Kinesis Data Firehose for analysis and storage.

 Security groups are the service or feature that meets the requirement of establishing a security layer in a VPC that will act as a firewall to control subnet traffic. Security groups are stateful firewalls that control the inbound and outbound traffic at the instance level. You can assign one or more security groups to each instance in a VPC, and specify the rules that allow or deny traffic based on the protocol, port, and source or destination. Security groups are associated with network interfaces, and therefore apply to all the instances in the subnets that use those network interfaces. Routing tables are used to direct traffic between subnets and gateways, not to filter traffic. Network ACLs are stateless firewalls that control the inbound and outbound traffic at the subnet level, but they are less granular and more cumbersome to manage than security groups. Amazon GuardDuty is a threat detection service that monitors your AWS account and workloads for malicious or unauthorized activity, not a firewall service.