Amazon Web Services Updated CLF-C02 Exam Questions and Answers by beauden

 D is correct because security groups are the AWS service or feature that can be used to control inbound and outbound traffic on an Amazon EC2 instance. Security groups act as a virtual firewall for the EC2 instance, allowing users to specify which protocols, ports, and source or destination IP addresses are allowed or denied. A is incorrect because internet gateways are the AWS service or feature that enable communication between instances in a VPC and the internet. They do not control the traffic on an EC2 instance. B is incorrect because AWS Identity and Access Management (IAM) is the AWS service or feature that enables users to manage access to AWS services and resources securely. It does not control the traffic on an EC2 instance. C is incorrect because network ACLs are the AWS service or feature that provide an optional layer of security for the VPC that acts as a firewall for controlling traffic in and out of one or more subnets. They do not control the traffic on an EC2 instance.

 The AWS service that requires the customer to patch the guest operating system is Amazon EC2. Amazon EC2 is a service that provides scalable compute capacity in the cloud, and allows customers to launch and run virtual servers, called instances, with a variety of operating systems, configurations, and specifications. The customer is responsible for patching and updating the guest operating system and any applications that run on the EC2 instances, as part of the security in the cloud. AWS Lambda, Amazon OpenSearch Service, and Amazon ElastiCache are not services that require the customer to patch the guest operating system. AWS Lambda is a serverless compute service that allows customers to run code without provisioning or managing servers. Amazon OpenSearch Service is a fully managed service that makes it easy to deploy, operate, and scale OpenSearch clusters in the AWS Cloud. Amazon ElastiCache is a fully managed service that provides in-memory data store and cache solutions, such as Redis and Memcached. These services are managed by AWS, and AWS is responsible for patching and updating the underlying infrastructure and software.

Amazon EC2 On-Demand Instances are instances that you pay for by the second, with no long-term commitments or upfront payments4. This option is suitable for applications that have unpredictable or intermittent workloads, such as the one described in the question. Amazon EC2 Standard Reserved Instances are instances that you purchase for a one-year or three-year term, and pay a lower hourly rate compared to On-Demand Instances. This option is suitable for applications that have steady state or predictable usage. 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. This option is not relevant for the application described in the question. Application Load Balancer is a type of load balancer that operates at the application layer and distributes traffic based on the content of the request. This option is not a service or feature to host the application, but rather to balance the traffic among multiple instances.

AWS CloudFormation is a service that allows you to model and provision your AWS and third-party application resources in a repeatable and predictable way. You can use AWS CloudFormation to create, update, and delete a collection of resources as a single unit, called a stack. You can also use AWS CloudFormation to manage your development and production environments in a consistent and efficient manner4.