AWS Interview Questions (13 Questions + Answers)

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Are you preparing for an AWS job interview? AWS hires talented people and gives them the tools and support that lets them change how the world works.

To help you ace your interview, here are some of the most common AWS interview questions along with sample answers. Learn these, and you’ll be one step ahead of other candidates.

1) Define and explain the three basic types of cloud services and the AWS products that are built based on them

AWS interview questions

Start by defining the three types of cloud services:

  • Infrastructure as a Service (IaaS)
  • Platform as a Service (PaaS)
  • Software as a Service (SaaS)

For each service type, mention at least one AWS product that represents it. This shows your familiarity with AWS offerings. Briefly explain why each service type is important and how it benefits users.

Sample answer:

"The three basic types of cloud services are IaaS, PaaS, and SaaS. IaaS, or Infrastructure as a Service, provides virtualized computing resources over the internet. AWS's EC2 (Elastic Compute Cloud) is an example, offering scalable computing capacity. PaaS, or Platform as a Service, offers a platform allowing customers to develop, run, and manage applications. AWS Elastic Beanstalk is a PaaS offering, simplifying the deployment of applications. Finally, SaaS, or Software as a Service, provides software applications over the internet. Amazon Chime, a communications service, is an example of SaaS, enabling video conferencing and chat functionalities. Each service type addresses different needs: IaaS offers flexible, scalable infrastructure; PaaS provides a platform for app development without managing infrastructure; and SaaS delivers ready-to-use software solutions."

This answer is effective because it covers all three service types and provides clear AWS examples for each. Mentioning specific AWS products demonstrates your familiarity with their ecosystem.

2) What is the relation between the Availability Zone and Region?

Start by defining what an AWS Region and an Availability Zone (AZ) are. Describe how Availability Zones are organized within Regions, then briefly mention why this relationship is significant for AWS services.

Sample answer:

"In AWS, a Region is a specific geographical location where AWS hosts its data centers. Each Region consists of multiple isolated locations known as Availability Zones (AZs). Availability Zones are physically separate data centers within a Region, each with redundant power, networking, and connectivity. They are designed to be interconnected through low-latency links. This setup ensures that if one AZ experiences issues, the others in the same Region can provide redundancy and continued service. For example, the US East (Northern Virginia) Region comprises several AZs, enabling customers to run applications and databases in multiple locations for better availability and fault tolerance. This relationship is crucial for ensuring high availability and disaster recovery in AWS services."

This is a great response because it provides clear, straightforward definitions of both a Region and Availability Zones. The answer also explains how AZs are part of a Region and their interconnectivity.

3) What are the steps involved in a CloudFormation Solution?

To answer this question, describe the key steps involved in creating and managing AWS CloudFormation solutions. Incorporate AWS-specific terms to demonstrate your familiarity with the platform.

Sample answer:

"The process of implementing a CloudFormation solution involves several key steps. First is the creation of a CloudFormation template in JSON or YAML format, which defines the AWS resources and their configurations. Next, you upload this template to CloudFormation to create a stack. The stack is a collection of AWS resources that CloudFormation manages as a single unit. Once the stack is created, CloudFormation provisions and configures the resources as specified in the template. You can then manage the stack by updating or deleting it as needed. If updates are required, you modify the template and update the stack, allowing CloudFormation to manage the changes. Deleting the stack removes all the resources associated with it. This process ensures a consistent and repeatable way to provision and manage AWS resources."

This response is effective because it outlines the steps in a logical order, from template creation to stack management. Incorporating terms like 'template', 'stack', and 'provision' also shows an in-depth knowledge of AWS CloudFormation.

4) How do you upgrade or downgrade a system with near-zero downtime?

Highlight AWS services and features that enable near-zero downtime, such as Elastic Load Balancing, Auto Scaling, and AWS Elastic Beanstalk. Then, outline a clear strategy that involves steps like testing in a staging environment, rolling updates, or blue/green deployments.

Sample answer:

"To achieve near-zero downtime during a system upgrade or downgrade, I use a combination of AWS services and deployment strategies. Firstly, I perform a test in a staging environment using AWS Elastic Beanstalk, ensuring the new version operates correctly. For the upgrade process, I utilize Elastic Load Balancing to distribute traffic across instances and employ Auto Scaling to adjust the capacity according to the load. I then implement a rolling update, where new instances with the upgraded system are gradually introduced, and old instances are removed. Alternatively, I use a blue/green deployment, where the new version (green) is deployed alongside the old version (blue), and traffic is slowly shifted to the green environment. This approach allows for monitoring performance and quick rollback if issues arise, ensuring continuous operation and minimal user impact. For downgrades, I follow a similar approach, ensuring a smooth transition back to the previous version."

This response mentions relevant AWS services, showing familiarity with the ecosystem. It also outlines a specific, actionable strategy for both upgrading and downgrading.

5) What are the tools and techniques that you can use in AWS to identify if you are paying more than you should be, and how to correct it?

For this question, discuss tools provided by AWS for monitoring and optimizing costs, such as AWS Cost Explorer, AWS Budgets, and Trusted Advisor, then explain how you can analyze spending patterns, identify underutilized resources, and spot opportunities for savings.

Sample answer:

"In AWS, effective cost management involves using tools like AWS Cost Explorer, AWS Budgets, and Trusted Advisor. With AWS Cost Explorer, I analyze spending patterns and usage trends to identify areas where costs can be reduced. AWS Budgets helps in setting custom budget alerts to monitor and manage spending. Trusted Advisor offers insights into where resources are underutilized. For correcting overspending, I assess if the current pricing models like On-Demand Instances are optimal, or if switching to Reserved Instances or Savings Plans can offer cost benefits. Regularly scaling resources based on demand and removing unused or idle resources also helps in cost optimization. For instance, downsizing instances or terminating orphaned EBS volumes can lead to significant savings. Lastly, ensuring that resources are in the right regions to avoid extra data transfer costs is crucial. This systematic approach to monitoring, analyzing, and optimizing resource usage ensures we pay only for what we need and use in AWS."

This response is effective because it clearly outlines the primary AWS tools designed for cost management. The answer also includes analyzing spending patterns and usage, which is crucial for identifying overspending.

6) What are the native AWS Security logging capabilities?

Mention AWS services specifically designed for security logging such as AWS CloudTrail, AWS CloudWatch, and Amazon VPC Flow Logs. Give a concise explanation of what each of these services does in terms of security logging.

Sample answer:

"AWS offers several native security logging capabilities to monitor and record activities within an AWS environment. AWS CloudTrail is pivotal for governance, compliance, and operational auditing as it logs all API calls made within the AWS platform, including calls made via the AWS Management Console, AWS SDKs, and command-line tools. AWS CloudWatch, on the other hand, monitors AWS resources and applications, providing logs that offer insight into system-wide performance changes and operational health. It can be configured to send alerts or automate actions based on defined metrics. Amazon VPC Flow Logs is another essential tool, capturing information about the IP traffic going to and from network interfaces in a Virtual Private Cloud (VPC). This data is vital for security and network troubleshooting. Together, these tools provide comprehensive logging capabilities, allowing for effective monitoring, troubleshooting, and analysis of security and operational issues within AWS."

This response specifically names and describes key AWS services used for security logging.

Each service is briefly explained, showing an understanding of their purposes and differences.

7) What is a DDoS attack, and what services can minimize them?

Start by defining what a DDoS attack is.

Discuss AWS services that are specifically designed to mitigate DDoS attacks, such as AWS Shield, AWS WAF (Web Application Firewall), and Amazon Route 53.

Briefly explain how each service contributes to minimizing the impact of DDoS attacks.

Sample answer:

"A DDoS attack is an attempt to disrupt normal traffic of a targeted server, service, or network by overwhelming it with a flood of Internet traffic from multiple compromised computer systems. AWS provides several services to help mitigate such attacks. AWS Shield, especially AWS Shield Advanced, offers protection against DDoS attacks by providing always-on detection and automatic inline mitigations. It can help protect applications running on AWS. AWS WAF (Web Application Firewall) enables you to monitor HTTP and HTTPS requests forwarded to Amazon CloudFront or an Application Load Balancer and helps block malicious requests. Also, Amazon Route 53 can be used to manage DNS traffic, which can distribute and absorb the traffic across a global network, thereby reducing the risk of any single point of failure. These services, used in conjunction, can significantly reduce the risk and impact of DDoS attacks on AWS-hosted applications."

This response is great for three reasons. It starts with a clear definition of what a DDoS attack is, and then it mentions and describes key AWS services relevant to DDoS mitigation. The answer also explains how each service helps in minimizing the impact of DDoS attacks.

8) You are trying to provide a service in a particular region, but you do not see the service in that region. Why is this happening, and how do you fix it?

Begin by mentioning that AWS services are not uniformly available in all regions and that service availability can vary. Briefly touch upon why some services might not be present in certain regions, such as local demand, data sovereignty laws, or infrastructure development.

Suggest practical steps to address this.

Sample answer:

"The absence of a specific AWS service in a particular region can occur because AWS does not uniformly distribute all its services across all regions. This might be due to varying local demand, data sovereignty laws, or the stage of infrastructure development in that region. To address this, first, verify the service availability in the desired region by checking the AWS Regional Services List. If the service isn't available, you can consider two options. One is to choose an alternative region where the service is available, ensuring it still meets your latency and legal requirements. The other option is to explore similar AWS services that might be available in your desired region and can fulfill your needs. It's also worth checking the AWS Roadmap or contacting AWS support to find out if there are plans to introduce the service in your region in the future."

This response is effective because it clearly explains why some services might not be available in certain regions. It also provides actionable steps one can take when faced with this issue.

9) How do you set up a system to monitor website metrics in real-time in AWS?

For this question, it’s important to highlight AWS services that are essential for real-time website monitoring such as Amazon CloudWatch, AWS CloudTrail, and AWS X-Ray.

Briefly outline how you would configure these services for real-time monitoring.

Sample answer:

"To monitor website metrics in real-time on AWS, I would primarily use Amazon CloudWatch, complemented by AWS CloudTrail and AWS X-Ray. CloudWatch allows for the collection and tracking of metrics, setting alarms, and automatically reacting to changes in AWS resources. I would set up CloudWatch to monitor key metrics like page load times, error rates, and user traffic patterns. AWS CloudTrail can be used for logging and tracking user activity and API usage, providing insights into who is accessing the website and how. AWS X-Ray would be crucial for tracing and analyzing user requests, helping in understanding performance bottlenecks, and identifying issues with the website. By integrating these tools, I can gain a comprehensive view of the website's performance and user interactions in real-time, allowing for quick response to any issues and continuous optimization of the user experience."

This response is great because it mentions specific AWS services designed for monitoring purposes. It also provides a brief overview of how to set up and utilize these services.

10) How would you approach troubleshooting a slow connection within the application?

Emphasize a step-by-step methodology to identify the root cause of the slow connection.

Mention relevant AWS tools that aid in troubleshooting, such as Amazon CloudWatch, AWS X-Ray, or VPC Flow Logs.

Sample answer:

"To troubleshoot a slow connection within an application on AWS, I'd start with a methodical approach to identify the root cause. Initially, I would use AWS CloudWatch to monitor network and application metrics, looking for any anomalies or performance degradation. AWS X-Ray can help in tracing the requests and pinpointing where the delays occur, whether it’s within the application or at the network level. If it's network-related, I'd check VPC Flow Logs to examine the network traffic patterns and identify any bottlenecks. On the application side, I would review the application logs to identify any slow-performing queries or inefficient code. I would also ensure the EC2 instances are adequately sized and the database performance is optimized. If the issue persists, I would consider whether the application needs to be scaled up or out to handle the load. Throughout the process, I would document the findings and actions taken, which not only helps in resolving the current issue but also in preventing similar issues in the future."

The answer reflects a structured approach to problem-solving. It specifically mentions using AWS tools for monitoring and diagnosing.

11) What are the differences between NAT Gateways and NAT Instances?

To answer this question, discuss the primary distinctions in terms of functionality, scalability, management, and cost. Mention typical scenarios where one might be preferred over the other.

Sample answer:

"NAT Gateways and NAT Instances in AWS serve the same purpose of enabling instances in a private subnet to connect to the internet or other AWS services while preventing the internet from initiating a connection with those instances. However, they differ significantly in several aspects. NAT Gateways are a managed service provided by AWS, offering high availability and built-in redundancy. They automatically scale up to 45 Gbps without any intervention, making them suitable for high-traffic scenarios. In contrast, NAT Instances are EC2 instances configured to perform NAT. They offer more flexibility in terms of configuration and allow the use of security groups. However, they require manual setup and maintenance, including scaling, patching, and monitoring. They also don't provide the same level of throughput as NAT Gateways. In terms of cost, NAT Gateways are generally more expensive but offer ease of use and better performance. NAT Instances might be more cost-effective for smaller workloads or where custom configurations are necessary."

The answer highlights the main differences in terms of management, scalability, and use cases. It also includes practical considerations like maintenance and cost, which are important in real-world applications.

12) Define Amazon EC2 regions and availability zones

Start by defining what an Amazon EC2 Region is, followed by what an Availability Zone (AZ) is.

Then, describe how Availability Zones are organized within Regions.

Sample answer:

"Amazon EC2 Regions are distinct geographical locations around the world, each hosting multiple isolated data centers. Each Region represents a separate geographic area designed to be completely independent from the other Regions. This design ensures fault tolerance and stability by geographically diversifying AWS infrastructure. Within each Region, there are Availability Zones (AZs), which are isolated data centers with their own power, cooling, and networking, to ensure redundancy and high availability. Each AZ is connected to others in the same Region through low-latency links. This setup allows users to operate production applications and databases that are more highly available, fault-tolerant, and scalable than would be possible from a single data center. For instance, hosting an application across multiple AZs in a Region can protect against failures within a single location. This structure is fundamental to the AWS cloud’s architecture, offering a balance between high availability and geographic reach."

The answer explains the relationship between Regions and AZs and their importance for fault tolerance and high availability. It also provides clear, straightforward definitions of both Regions and Availability Zones.

13) Mention the different types of instances in Amazon EC2 and explain its features

Mention the broad categories of EC2 instances like General Purpose, Compute Optimized, Memory Optimized, Storage Optimized, and Accelerated Computing.

For each category, briefly describe the key features and typical use cases.

Sample answer:

"Amazon EC2 provides a variety of instance types optimized for different use cases:

General Purpose Instances (e.g., T3, M5): These are balanced in terms of compute, memory, and networking resources and are suitable for a wide range of applications like web servers and code repositories.

Compute Optimized Instances (e.g., C5): These instances offer high performance processors and are ideal for compute-intensive applications like batch processing and gaming servers.

Memory Optimized Instances (e.g., R5, X1): They are designed for memory-intensive tasks such as high-performance databases and big data processing.

Storage Optimized Instances (e.g., D2, H1): These are optimized for workloads requiring high, sequential read and write access to large datasets on local storage.

Accelerated Computing Instances (e.g., P3, G4): They use hardware accelerators, or co-processors, such as GPU for graphics and data processing tasks like machine learning and 3D visualization.

Each type is tailored to specific workload requirements, helping users to optimize performance and cost for their applications."

The answer encompasses the main categories of EC2 instances. It describes the features and typical use cases for each type, demonstrating an understanding of their purpose.

What to wear to an AWS job interview to get hired

According to Amazon’s job resources page, you should wear something comfortable and casual. While some roles in our fulfillment centers may require certain clothing for safety reasons (such as closed-toed shoes), in most of our offices people wear everyday clothes. Amazon is interested in what you have to say, not what you’re wearing.

For an AWS job interview, go for smart casual attire, which is a blend of professional and informal clothing. It’s polished yet relaxed. Here's an example for both men and women:

For Men:

  • A button-down shirt or a smart polo shirt. It could be a solid color or a subtle pattern.
  • Chinos or smart trousers in a neutral color like navy, gray, or beige.
  • A blazer or sportcoat can be added for a more refined touch, though it's optional.
  • Shoes could be loafers, brogues, or clean, minimalist sneakers.
  • Accessories like a leather belt and a wristwatch can complement the outfit.

For Women:

  • A blouse or a smart top, which can be paired with a cardigan or a tailored blazer.
  • Skirt at knee-length or tailored trousers or dark-wash jeans in a straight or slim fit.
  • Footwear options include flats, loafers, ankle boots, or heels that are comfortable.
  • Simple jewelry like stud earrings or a delicate necklace adds a touch of elegance.
  • A structured handbag or a sleek tote bag to complete the look.

In both cases, the key is to balance comfort with sophistication. The outfit should be neat, well-fitted, and suitable for a semi-professional setting.

What to expect from an AWS job interview

Knowing what to expect from an AWS interview can make or break the outcome.

I asked my friend who's been through the AWS job interview process. He told me that the key thing Amazon looks for is whether you're coachable or not.

Focus on both technical and soft skill questions. Amazon places a strong emphasis on the STAR format for responses. So, as you prepare, think about how your experiences relate to Amazon's leadership principles and highlight these in your story, especially when discussing the resolution outcome.

Your first interview will likely be technical. Understanding Amazon's principles is crucial; they might include a question based on these. According to my friend, this round felt more like a technical screening. If you progress past this, you need to know the leadership principles thoroughly and have examples ready for each.

The second round of interviews is extensive, lasting about 3.5 hours. It mostly involves behavioral questions, with one technical question at the end, conducted by five different people.

Remember, your answers don’t have to be limited to professional experiences. My friend, for example, talked about my experiences with home ownership and personal AWS projects. Amazon is looking for a cultural fit and someone who embodies their principles and can communicate effectively.

If you’re doing an online interview, ensure your webcam and mic are working, and that your area is clean. Stay calm, smile, and try not to be too nervous.

Prepare a Google Doc with your questions and answers in the STAR format and practice them verbally without notes. I recommend staging mock video interviews with friends and family to refine your responses and body language. Prepare 2-3 stories for each leadership principle or question.

Most importantly avoid exaggerating or fabricating your experiences. Be honest about your strengths and weaknesses. The interviewers take notes and discuss them collectively after your interview.

They're not just looking for technical expertise; they want people who can thrive in their teams and culture with the right resources. If you're a good fit for Amazon, it will naturally come through in the interview.

Reference this article:

Practical Psychology. (2023, December). AWS Interview Questions (13 Questions + Answers). Retrieved from

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