Common AWS interview questions
Question 1
What is Amazon EC2 and what are its main features?
Answer 1
Amazon EC2 (Elastic Compute Cloud) is a web service that provides resizable compute capacity in the cloud. Its main features include scalability, flexibility, pay-as-you-go pricing, and the ability to launch virtual servers as needed. EC2 supports various instance types, security groups, and integration with other AWS services.
Question 2
How does AWS S3 ensure data durability and availability?
Answer 2
AWS S3 ensures data durability by automatically storing data across multiple devices in multiple facilities within a region. It is designed for 99.999999999% (11 9's) durability and 99.99% availability over a given year. S3 also supports versioning and cross-region replication for additional protection.
Question 3
What is IAM in AWS and why is it important?
Answer 3
IAM (Identity and Access Management) is a service that helps you securely control access to AWS resources. It allows you to create and manage users, groups, and permissions. IAM is important because it enables fine-grained access control, ensuring that only authorized users can access specific resources.
Describe the last project you worked on as a AWS, including any obstacles and your contributions to its success.
The last project I worked on involved designing and deploying a scalable web application on AWS using EC2, S3, RDS, and Lambda. I implemented a multi-AZ architecture for high availability and used CloudFormation for infrastructure as code. Security was enhanced with IAM roles and encrypted storage. The project improved performance and reduced operational costs for the client.
Additional AWS interview questions
Here are some additional questions grouped by category that you can practice answering in preparation for an interview:
General interview questions
Question 1
What is the difference between a security group and a network ACL in AWS?
Answer 1
A security group acts as a virtual firewall for EC2 instances to control inbound and outbound traffic at the instance level, while a network ACL (Access Control List) operates at the subnet level and controls traffic entering and leaving the subnet. Security groups are stateful, meaning return traffic is automatically allowed, whereas network ACLs are stateless and require explicit rules for both inbound and outbound traffic.
Question 2
How do you monitor AWS resources and applications?
Answer 2
AWS provides several monitoring tools, such as Amazon CloudWatch, which collects and tracks metrics, logs, and events for AWS resources and applications. CloudWatch allows you to set alarms, visualize metrics, and automate responses to changes in your environment. Other tools include AWS CloudTrail for auditing API calls and AWS Config for resource configuration tracking.
Question 3
What is an AWS VPC and what are its key components?
Answer 3
An AWS VPC (Virtual Private Cloud) is a logically isolated section of the AWS cloud where you can launch AWS resources in a virtual network. Key components include subnets, route tables, internet gateways, NAT gateways, and security groups. VPCs provide control over network configuration, including IP address ranges and connectivity.
AWS interview questions about experience and background
Question 1
What AWS certifications do you hold and how have they helped you in your career?
Answer 1
I hold the AWS Certified Solutions Architect – Associate and AWS Certified Developer – Associate certifications. These certifications have deepened my understanding of AWS services and best practices, and have helped me design and implement robust cloud solutions. They have also increased my credibility with employers and clients.
Question 2
Can you describe a challenging AWS project you worked on and how you overcame obstacles?
Answer 2
I worked on migrating a legacy application to AWS, which involved complex dependencies and tight deadlines. I overcame obstacles by breaking down the migration into phases, using AWS migration tools, and collaborating closely with stakeholders. Regular testing and monitoring ensured a smooth transition with minimal downtime.
Question 3
How do you stay updated with the latest AWS features and best practices?
Answer 3
I stay updated by following AWS blogs, attending webinars, and participating in AWS re:Invent and other conferences. I also engage with the AWS community through forums and user groups, and regularly review AWS documentation and release notes.
In-depth AWS interview questions
Question 1
Explain how you would design a highly available and fault-tolerant architecture on AWS.
Answer 1
To design a highly available and fault-tolerant architecture, I would use multiple Availability Zones (AZs) for redundancy, deploy resources across these AZs, and use Elastic Load Balancers to distribute traffic. I would also leverage Auto Scaling to handle variable loads and use managed services like RDS Multi-AZ deployments for databases. Regular backups, monitoring, and disaster recovery planning are also essential.
Question 2
How would you secure sensitive data stored in AWS?
Answer 2
To secure sensitive data, I would use encryption at rest and in transit, leveraging AWS Key Management Service (KMS) for key management. I would implement strict IAM policies, enable logging and monitoring, and use services like AWS Secrets Manager for managing credentials. Regular audits and compliance checks are also important for maintaining security.
Question 3
Describe the process of migrating an on-premises application to AWS.
Answer 3
Migrating an on-premises application to AWS involves assessment, planning, and execution. First, I would analyze the current environment and dependencies, then design the target architecture on AWS. The migration could use tools like AWS Migration Hub, Database Migration Service, and Server Migration Service, followed by testing, optimization, and cutover to production.