Interview questions on Designing and deploying scalable and highly available and fault-tolerant systems on AWS

Here are some commonly asked AWS Certification interview questions regarding the Designing and deploying scalable, highly available and fault-tolerant systems on AWS

1. What is the AWS global infrastructure?

The AWS Global Infrastructure is a network of multiple, interconnected data centers located in different regions around the world. The infrastructure provides low latency and high throughput performance for customers, enabling them to deploy their applications and data closer to their end-users.

2. What is Amazon EC2, and how does it provide scalable computing capacity in the cloud?

Amazon Elastic Compute Cloud (Amazon EC2) is a scalable computing service that provides resizable computing capacity in the cloud. EC2 allows customers to launch virtual machine instances, and adjust the number of instances to meet the demands of their applications. EC2 provides scalable computing capacity, as it allows customers to quickly and easily scale their computing resources up or down as needed.

3. What is Amazon S3, and how does it provide scalable object storage in the cloud?

Amazon Simple Storage Service (Amazon S3) is an object storage service that provides scalable and durable storage in the cloud. S3 allows customers to store and retrieve any amount of data, at any time, from anywhere on the web. S3 provides scalable object storage, as it automatically scales to accommodate growth in data and automatically replicates data across multiple availability zones for durability.

4. What is Amazon S3 and how can it be used for high availability?

Amazon S3 (Simple Storage Service) is an object storage service that provides scalable and durable storage for customers’ data. It can be used for high availability by replicating data across multiple availability zones within a region, or across multiple regions. This provides automatic failover and increased durability, ensuring that data remains available even in the event of an outage or failure.

5. What is Amazon EC2 Auto Scaling?

Amazon EC2 Auto Scaling is a service that automatically adjusts the capacity of Amazon EC2 instances based on the demand for resources. The service can be configured to automatically increase or decrease the number of instances in response to changes in demand, ensuring that applications are always running at optimal performance and availability.

6. What is Amazon Route 53?

Amazon Route 53 is a highly available and scalable Domain Name System (DNS) web service. It can be used to route users to websites, web applications, and other resources, ensuring high availability and reliability. The service also supports various routing policies, such as simple round-robin, latency-based, and geo-proximity, allowing customers to choose the best policy for their specific needs.

7. What is Amazon RDS and how can it be used for high availability?

Amazon RDS (Relational Database Service) is a managed database service that makes it easy to set up, operate, and scale relational databases in the cloud. It can be used for high availability by creating a Multi-AZ (availability zone) deployment, which provides automatic failover in the event of a hardware failure or an outage in the primary instance. This helps ensure that the database remains available and accessible to applications, even during unplanned events.

8. What is Amazon CloudFront?

Amazon CloudFront is a content delivery network (CDN) that speeds up the delivery of static and dynamic web content, such as HTML pages, images, videos, and APIs. It integrates with other Amazon Web Services, such as S3 and EC2, to provide low latency and high data transfer speeds for customers’ applications.

9. What is Amazon ELB and how does it provide high availability?

Amazon ELB (Elastic Load Balancer) is a load balancing service that distributes incoming application traffic across multiple EC2 instances, improving application availability and fault tolerance. ELB automatically detects unhealthy instances and routes traffic to healthy instances, ensuring that applications are always available and accessible to users.

10. What is Amazon VPC?

Amazon VPC (Virtual Private Cloud) is a virtual network dedicated to a customer’s AWS account. It enables customers to launch AWS resources into a virtual network, isolated from the public Internet. VPC provides complete control over the virtual networking environment, including the selection of IP address ranges, creation of subnets, and configuration of route tables and network gateways.

11. What is Amazon SNS?

Amazon SNS (Simple Notification Service) is a fully managed messaging service for sending messages to multiple subscribers. It can be used for a variety of applications, such as delivering SMS messages, sending notifications to mobile devices, or fanning out messages to multiple endpoints. SNS ensures high availability and durability by automatically replicating messages to multiple availability zones.

12. What is Amazon SQS and how does it provide high availability?

Amazon SQS (Simple Queue Service) is a fully managed message queuing service that enables decoupled communication between distributed application components. It provides high availability by automatically distributing messages across multiple availability zones, ensuring that messages are always available and can be delivered even in the event of a failure. SQS also provides a range of features for ensuring the reliability and durability of messages, including message persistence and guaranteed delivery.

13. What is Amazon SES and how does it provide high availability?

Amazon SES (Simple Email Service) is a highly scalable and cost-effective email sending and receiving service. It provides high availability by automatically routing emails through multiple servers and data centers, ensuring that emails are delivered even in the event of a failure. SES also provides features such as email tracking and delivery reports, enabling customers to monitor the delivery of their emails.

14. What is Amazon DynamoDB and how does it provide high availability?

Amazon DynamoDB is a fully managed NoSQL database service that provides fast and predictable performance with seamless scalability. It provides high availability by automatically replicating data across multiple availability zones, ensuring that data is always available even in the event of a failure. DynamoDB also supports configurable backup and restore options, enabling customers to backup and restore their data as needed.

15. What is Amazon CloudWatch?

Amazon CloudWatch is a monitoring service for AWS resources and the applications that run on the AWS cloud. It provides operational visibility and insights for customers, enabling them to monitor their resources and applications in real-time. CloudWatch provides high availability by automatically replicating data across multiple availability zones, ensuring that monitoring data is always available even in the event of a failure.

16. What is Amazon S3 Transfer Acceleration?

Amazon S3 Transfer Acceleration is a feature of S3 that speeds up transfers of large files to and from S3 using Amazon CloudFront’s globally distributed edge locations. It provides fast, reliable, and secure transfers, making it easier for customers to transfer large amounts of data to S3 over long distances. S3 Transfer Acceleration leverages Amazon CloudFront’s globally distributed network to upload data to the nearest edge location, which then transfers the data to S3. This results in faster upload speeds compared to uploading directly to S3. S3 Transfer Acceleration is highly available and scalable, ensuring that customers can transfer large amounts of data quickly and reliably.

17. What is Amazon EBS Snapshots and how do they provide data protection and high availability?

Amazon EBS (Elastic Block Store) Snapshots are point-in-time copies of EBS volumes. They provide a simple and efficient way to backup and protect data on EBS volumes. EBS Snapshots are stored in S3, providing durable and highly available storage for customers’ backups. Additionally, EBS Snapshots can be used to create new EBS volumes, enabling customers to quickly recover from data loss or to create new instances with the desired data. EBS Snapshots also provide versioning, enabling customers to keep multiple snapshots of their data and revert to previous versions as needed.

18. What is Amazon Auto Scaling and how does it provide high availability?

Amazon Auto Scaling is a service that automatically adjusts the capacity of Amazon EC2 instances based on user-defined policies, schedules, and health checks. It enables customers to automatically scale their applications up or down based on demand, ensuring that their applications always have the resources they need to function optimally. Auto Scaling provides high availability by automatically replacing failed or unhealthy instances, ensuring that applications are always available and accessible to users.

19. What is Amazon RDS and how does it provide high availability?

Amazon RDS (Relational Database Service) is a fully managed relational database service that makes it easy to set up, operate, and scale a relational database in the cloud. It provides high availability by automatically replicating data across multiple availability zones, ensuring that data is always available even in the event of a failure. RDS also supports multi-AZ deployments, which provide automatic failover in the event of a failure.

20. What is Amazon ECS and how does it provide high availability?

Amazon ECS (Elastic Container Service) is a fully managed container orchestration service that makes it easy to run, stop, and manage Docker containers on the AWS cloud. It provides high availability by automatically replacing failed containers, ensuring that applications are always running and accessible to users. ECS also supports service auto-scaling, which automatically adjusts the number of running containers based on demand, further improving application availability and reliability.

21. What is Amazon Route 53 and how does it provide high availability?

Amazon Route 53 is a highly scalable and available Domain Name System (DNS) service. It provides high availability by automatically routing traffic to the closest available endpoint, ensuring low latency and high availability for customers’ applications. Route 53 also supports failover and health checking, enabling customers to automatically route traffic away from failed resources, further improving the availability and reliability of their applications.

22. What is Amazon Elasticache and how does it provide high availability?

Amazon Elasticache is a fully managed in-memory caching service that makes it easy to deploy, operate, and scale an in-memory cache in the cloud. It provides high availability by automatically replicating data across multiple cache nodes, ensuring that data is always available even in the event of a failure. Elasticache also supports multi-AZ deployments, which provide automatic failover in the event of a failure, further improving the availability and reliability of customers’ applications.

23. What is Amazon S3 Intelligent-Tiering and how does it provide high availability?

Amazon S3 Intelligent-Tiering is a storage class that automatically moves data between two access tiers (frequent and infrequent access) based on changing access patterns. It provides high availability by automatically replicating data across multiple availability zones, ensuring that data is always available even in the event of a failure. S3 Intelligent-Tiering also supports versioning, enabling customers to keep multiple versions of their data and revert to previous versions as needed.

24. What is Amazon EC2 Spot Instances and how does it provide cost savings?

Amazon EC2 Spot Instances are unused EC2 instances that are available for bidding at a lower price than On-Demand instances. Customers can bid on Spot Instances and run them as long as their bid price exceeds the current Spot price. This provides cost savings for customers by allowing them to access excess EC2 capacity at a lower cost. EC2 Spot Instances also provide high availability by automatically replacing failed instances, ensuring that applications are always running and accessible to users.

25. What is Amazon EFS and how does it provide high availability?

Amazon EFS (Elastic File System) is a fully managed file storage service for use with Amazon EC2 instances. It provides high availability by automatically replicating data across multiple availability zones, ensuring that data is always available even in the event of a failure. EFS also supports auto-scaling, enabling customers to dynamically adjust the amount of storage capacity they have available, further improving the reliability and availability of their applications.

26. What is Amazon CloudFront and how does it provide high availability?

Amazon CloudFront is a content delivery network (CDN) service that speeds up the delivery of static and dynamic web content, such as HTML, CSS, JavaScript, and images. It provides high availability by automatically routing traffic to the closest available edge location, ensuring low latency and high availability for customers’ applications. CloudFront also supports custom error pages, enabling customers to provide a better user experience even in the event of a failure.

27. What is Amazon SNS and how does it provide high availability?

Amazon SNS (Simple Notification Service) is a fully managed messaging service that makes it easy to send notifications to distributed systems, applications, and users. It provides high availability by automatically replicating messages across multiple availability zones, ensuring that messages are always delivered even in the event of a failure. SNS also supports message filtering, enabling customers to subscribe to only the messages that are relevant to their applications, further improving the reliability and availability of their systems.

28. What is a fault-tolerant system, and why is it important in the cloud environment?

A fault-tolerant system is a system that is designed to continue functioning even in the event of one or more failures. In the cloud environment, it is important to have a fault-tolerant system because cloud services can experience outages or failures, and it is crucial to ensure that the applications and systems running on those services remain available to users.

29. What is Amazon EC2 Auto Recovery, and how does it provide fault tolerance?

Amazon EC2 Auto Recovery is a feature of Amazon EC2 that automatically replaces failed Amazon EC2 instances. This helps to ensure high availability of applications and systems running on Amazon EC2, as it eliminates the need for manual intervention to recover from a failure.

30. What is Amazon S3 Cross-Region Replication, and how does it provide fault tolerance?

Amazon S3 Cross-Region Replication is a feature of Amazon S3 that automatically replicates data to another S3 bucket in a different AWS region. This helps to ensure high data availability and data protection, as it provides an additional copy of data in case of a failure or outage in the primary region.

31. What is Amazon EBS Snapshots, and how does it provide data protection and disaster recovery?

Amazon EBS Snapshots is a feature of Amazon EBS (Elastic Block Store) that enables customers to create point-in-time snapshots of their EBS volumes. These snapshots can be used to create new EBS volumes, and can also be used for data backup and disaster recovery purposes. This helps to ensure that data is protected, even in the event of a failure or disaster.

32. What is Amazon RDS Multi-AZ Deployments, and how does it provide high availability and disaster recovery?

Amazon RDS Multi-AZ Deployments is a feature of Amazon RDS that enables customers to run their relational databases across multiple availability zones. This provides high availability and disaster recovery, as it ensures that the database remains available in the event of a failure or disaster in one availability zone.

33. What is Amazon CloudWatch Alarms, and how does it provide monitoring and automated recovery from failures?

Amazon CloudWatch Alarms is a feature of Amazon CloudWatch that enables customers to monitor their resources and take automated actions in response to changes in the state of those resources. This provides monitoring and automated recovery from failures, as it allows customers to set up alarms that trigger automated actions, such as starting or stopping instances, in response to failures or changes in resource state.

34. What is Amazon Elastic Load Balancer, and how does it provide load balancing and fault tolerance?

Amazon Elastic Load Balancer is a service that automatically distributes incoming application traffic across multiple Amazon EC2 instances. This provides load balancing and fault tolerance, as it ensures that traffic is evenly distributed across instances, and it can automatically redirect traffic to healthy instances in the event of a failure.

35. What is Amazon VPC (Virtual Private Cloud), and how does it provide network isolation and security for applications?

Amazon VPC is a service that enables customers to launch Amazon Web Services resources into a virtual network that is isolated from the public Internet. This provides network isolation and security for applications, as it enables customers to control network access to their resources, and it provides an additional layer of security for their applications and data.

36. What is Amazon Route 53, and how does it provide a highly available and scalable DNS infrastructure?

Amazon Route 53 is a highly available and scalable domain name system (DNS) service. It provides a reliable and low-latency way of routing end-users to internet applications by translating domain names into IP addresses. Route 53 automatically routes traffic to healthy endpoints, and it supports geographic routing and failover, providing a highly available and scalable DNS infrastructure.

37. What is Amazon Auto Scaling, and how does it provide automatic scalability and fault tolerance for applications?

Amazon Auto Scaling is a service that automatically adjusts the number of Amazon EC2 instances in response to changes in demand for an application. It provides automatic scalability and fault tolerance for applications, as it automatically adds or removes instances based on predefined conditions, ensuring that applications remain available and responsive even during periods of increased demand.

38. What is Amazon DynamoDB, and how does it provide a highly available and scalable NoSQL database service?

Amazon DynamoDB is a fully managed NoSQL database service that provides fast and predictable performance with seamless scalability. It provides a highly available and scalable database service, as it automatically replicates data across multiple availability zones, and it supports global tables, which allow customers to run multi-region, multi-master databases.

39. What is Amazon S3 Transfer Acceleration, and how does it provide faster data transfers and improved reliability?

Amazon S3 Transfer Acceleration is a feature of Amazon S3 that enables customers to transfer large amounts of data into S3 over the AWS Global Accelerator network. This provides faster data transfers and improved reliability, as it leverages the AWS backbone network to achieve faster transfer speeds and improved reliability compared to traditional Internet transfers.

40. What is Amazon Redshift, and how does it provide a highly available and scalable data warehousing solution?

Amazon Redshift is a fully managed data warehousing service that enables customers to quickly analyze large amounts of data. It provides a highly available and scalable data warehousing solution, as it automatically replicates data across multiple nodes, ensuring high availability, and it supports automatic scaling of compute and storage resources, providing scalability as data and performance needs change.