AWS Interview Questions and Answers

Amazon Web Services, AWS Interview Questions

These AWS questions have been designed for various interviews, competitive exams and entrance tests. We have covered questions on both basic and advanced concepts which will help you improve your skills to face interview questions on AWS.

Who are these AWS interview questions designed for?

All the AWS developers, AWS Cloud Engineers, AWS Solution Architects, AWS Cloud Architects, AWS Data Engineers, AWS Architects etc. will find these questions extremely useful. All freshers, BCA, BE, BTech, MCA and college students wanting to make a career in AWS will be highly benefited by these questions.

1. Define Amazon Web Services or AWS.

AWS stands for Amazon Web Services. It is a platform that provides Secure Cloud Services, Storage and Content Delivery Services, Compute and Networking Services, Database Services and other services to help business grow and develop. With AWS, you don’t have to maintain or buy servers. You can access unlimited resources and pay for only what you use.

2. What are the different services offered by cloud computing?

Cloud computing services fall into 3 categories:

Platform as a Service (PaaS) - It is a cloud-computing offering where a vendor offers access to a cloud-based environment in which users can build and deliver applications.

Infrastructure as a Service (IaaS) - It is a cloud-computing offering where a vendor offers storage, networking, servers and other computing resources in the cloud.

Software as a Service (SaaS) - It is a cloud-computing offering where a vendor offers cloud-based software.

3. What are the main components of AWS?

The key components of AWS are:  

Simple Email Service: It allows sending e-mail using RESTFUL API call or via regular SMTP

Route 53: This is a DNS (Domain Name Service) web service.

Simple Storage Device (S3): It is a storage device and most widely used utility among all the AWS Services

Elastic compute cloud (EC2): It provides on-demand computing resource for hosting applications.

Elastic Block Store (EBS): It is a block storage system used to store persistent data.

Cloud watch: It provides real-time monitoring of AWS resources and hosted applications.

4. What is Buffer in AWS?

Buffer is used to make system more efficient against the burst of traffic or load. It synchronizes different component. Usually, components receive and process the requests in an unbalanced way. With the help of buffer, the components will be balanced and will work at the same speed to provide faster services.

5. What is Amazon S3 and Amazon EC2?

S3 stands for Simple Storage Service. Amazon S3 is cloud storage for the Internet and used for storing and retrieving data at anytime and anywhere on the web. S3 scales storage according to your requirement and you only pay for the storage you use.

EC2 - It is a cloud web service that is used to host the application

6. What is AMI? Explain the relationship between an instance and AMI?

An Amazon Machine Image (AMI) is used to create virtual servers in the AWS environment. It is actually a template that contains a software configuration. From an AMI, you can launch an instance that is the replica of the AMI running in the cloud as a virtual server.

An instance is a copy of the AMI running as a virtual server in the cloud. You can launch multiple instances from a single AMI to support the hardware of the host computer used for the instance.

7. What is SQS? What are the types of queues in SQS?

Amazon SQS stands for Simple Queue Service. It is fully managed message queuing service. It offers a reliable, highly scalable, hosted queue for storing messages as they travel between applications. Using Amazon SQS, you transmit any volume of messages between software components without losing messages. There are two types of Queue:

Standard Queues (default)
SQS offers a standard queue as the default queue type. It allows you to have an unlimited number of transactions per second.  Standard queue offers at least one delivery and maximum throughput.

FIFO Queues (First-In-First-Out)
FIFO Queues provide exactly-once processing, which means that each message is delivered once and remains available until a consumer processes it and deletes it. It preserves the exact order in which messages are sent and received. It does not allow duplicates to be introduced into the Queue.

8. What is meant by cloud watch? What are the levels of monitoring Cloudwatch offers?

Amazon CloudWatch is a built-in monitoring system in AWS designed to provide real-time monitoring of AWS resources and hosted applications. With CloudWatch, you can collect and access metrics, collect and monitor log files and set alarms.

Cloudwatch offers two levels of monitoring: basic monitoring and detailed monitoring. The basic monitoring will come to you at free of cost, but when it comes to detailed control, you need to pay for it.

9. What is AWS Lambda?

AWS Lambda is a serverless computing service provided by AWS. It is an event-driven that runs your code in response to events and provides resources automatically based on your workload. It is a serverless architecture so one need not worry about provisioning or managing servers.  

10. What is Geo Restriction in CloudFront?

Geo Restriction in Amazon CloudFront allows to choose the regions where you want Amazon CloudFront to deliver your content. It is also known as geo-blocking which blocks the users in particular geographic locations from accessing the content from specific regions.

11. What are Edge Locations in AWS?

Edge locations are AWS Data Centers. They are intermediate sites between the end users and servers to access the services from AWS. Edge locations are mainly used by AWS CloudFront for caching the content for faster delivery to users at any location.

12. Differentiate between vertical and horizontal scaling in AWS.

Horizontal scaling involves adding compute resources in the pool of existing resources so that the workload and processing is shared among multiple devices.

Vertical scaling involves adding more power (CPU, RAM) to an existing machine.