AWS Interview Questions and Answers

 

Q1. Define and explain the main types of cloud services and all the AWS products that have been built on them. 

There are types of cloud services. These can be basically categorized as 

• Computing
• Networking 
• Storage

Each type of service has specific AWS products built around them. The most common ones are:

• Computing: Lightsat, EC2, Lambda, Auto-Scaling and Elastic Beanstalk.
• Networking: Amazon Cloudfront, VPC and Route 53.
• Storage: Elastic File System, S3, Elastic Block Storage and Glacier.

Q2. What is auto-scaling?

Auto-scaling can be defined as a function that enables users to provision and launch new instances whenever the demand arises. Auto-scaling allows automatic increasing and decreasing of resource capacity, as is directly proportional to the demand.

Q3. What is geo-targeting in CloudFront?

You might have seen that when you move to a different place, the ads and content you see online change accordingly. This is what the primary purpose of geo-targeting is.

 

It enables businesses to show audiences personalized content without having to change the URL. This allows businesses to create content for highly segmented audiences within a particular geographical location and address their pain points. 

Q4. In AWS, which techniques and tools can you use to find out if you’re paying more than necessary? Is there a way to correct this?

You can use several resources to ensure you are paying the right amount for the services and products you are using.

• The Top Services Table: This dashboard within the cost management console will show businesses the five services they use the most. It will also show them their total spending on these resources.
• Cost Explorer: These services help businesses analyze and view their usage costs over the past 13 months. It also gives a forecast of expenditure for the next three months. 
• AWS Budgets: AWS Budgets allows businesses to budget their services. It enables them to also keep a check on whether they are within budget with their current plan along with the details of service usage.
• Cost Allocation Tags: These tags help businesses to identify any resource that has incurred extra costs in a specific month. You can organize your resources and track your costs using Cost Allocation Tags.

Q5. Are there alternative tools for logging into the cloud environment besides the console?

There are several tools you can use to log into the AWS Cloud. These are:

• AWS CLI for CMD
• AWS CLI for Windows
• AWS CLI for Linux
• Eclipse
• Putty
• AWS SDK

Q6. Which services can help in creating a centralized logging solution?

Businesses can use Amazon CloudWatch Logs to create centralized logging solutions, use Amazon S3 to store them, and visualize them using Amazon Elastic Search. You can also use Kinesis Firehose for moving the data from S3 to ElasticSearch.

Q7. What are DDoS attacks? Which services can be used to minimize them?

A DDoS is a type of cyberattack where a perpetrator gains access to a website, then generates multiple sessions to prevent other legitimate guests from accessing the service. Businesses can use several native AWS tools to prevent DDoS attacks. These are

• AWS WAF
• AWS Shield
• Amazon CloudFront
• Amazon Route53
• VPC
• ELB

Q8. Consider this situation. While trying to provide a particular service in a region, you can’t see the service within the region. What is the cause and solution to this problem?

All AWS solutions are not available in every region. When Amazon launches a new service, it is not instantly published or launched in every region. Instead, Amazon starts small and slowly spreads to other places. If a particular service is not available in a certain area, there is a good chance the service has not been launched in your area.

 

One way to get this service is by switching to a nearby area offering the service.

Q9: How can a system be set up for monitoring real-time metrics in AWS?

Businesses can use Amazon CloudWatch to monitor the status of several AWS solutions and events. CloudWatch also allows the monitoring of:

• Changes in the state in EC2
• Auto-scaling lifecycle events
• Console sign-in instances
• Scheduled events
• AWS API calls

Q10. List and differentiate between the types of AWS virtualization.

There are three categories of virtualization in AWS. These are

• HVM - Hardware Virtual Machine: This is hardware that is completely virtualized, which means each virtual machine acts separately from the other. An HVM boots with the execution of a master boot record in an image’s root block device.
• PV - Paravirtualization: The bootloader Paravirtualization-GRUB boots PV AMIs. PV-GRUB loads kernels that are specified on the menu.
• Paravirtualization on HVM: This type of virtualization allows operating systems to take advantage of network and storage I/ O that is available via the host.

ALSO READ: AWS Certifications List and Cost 2022

Q11. Do you know any AWS services that aren’t region-specific?

• IAM
• Web Application Firewall
• CloudFront
• Route 53

Q12. Name the types of EC2 instances categorized by cost.

Based on costs, there are three types of instances in EC2.

• Spot Instances: These instances can be bought by bidding. They are cost-effective in the long run.
• On-demand Instances: These are cheap when used short-term, but not in the long term.
• Reserved Instances: These are ideal for businesses looking for instances to use for more than a year.

Q13. Given that you shouldn’t have to copy your key each time you log in, how will you set up SSH agent forwarding?

There are three simple steps to achieve this.

• Go to PuTTY Configuration on your system
• SSH > Auth
• Enable SSH agent forwarding

Q14. What are Solaris and AIX? Are they available with AWS?

Solaris and AIX are operating systems, but they aren’t available with AWS due to their current limitations.

Solaris uses the architecture of a SPARC processor, which isn’t currently supported by public cloud platforms.

AIX runs on Power CPU only and not Intel, which means it cannot be used with EC2.

Q15. How should you configure CloudWatch for the recovery of EC2 instances?

• Using CloudWatch, create an Alarm.
• Head to Define Alarm, and then to Actions
• Choose ‘Recover This Instance’

Q16. How can you log in to or recover an EC2 instance in a situation where the key is lost?

If you lose the key, the following steps can help recover the EC2 instance in question.

• Verify that EC2Config is running
• Detach the instance’s root volume
• Attach this volume to a temporary instance
• Modify the configuration file
• Restart the instance you were looking to recover.

Q17. How can a user be allowed to get access to a specific bucket?

To give access to a user, there are four steps to be followed in the following order.

• Categorize existing instances
• Define how each authorized user can manage particular servers
• Lockdown any tags
• Attach all policies to IAM users

Q18. If VPC is unable to resolve a server via DNS, what could the problem be, and how can it be fixed?

This problem can easily resolve itself. All you have to do is enable DNS hostname resolution.

 

Additional Read: How To Build a Career with AWS Certifications?

Q19. Define and describe some VPC security features and products.

There are several security products available in VPC. Here are some of the most popular ones. 

• Security groups: These act as firewalls for EC2 instances. They control outbound and inbound traffic at an instance level.
• Network access control lists: This feature covers subnets like a firewall, controlling outbound and inbound traffic at a subnet level.
• Flow logs: These logs capture outbound and inbound traffic from your VPC’s network interface.

Q20. How can Amazon VPC be monitored?

There are two ways to monitor Amazon VPC. This is by using either of the following:

• CloudWatch and CloudWatch logs
• VPC Flow Logs

Q21. How can an existing instance be added to new Auto Scaling groups?

This can be achieved with the following steps.

• Open the EC2 console
• Select the desired instance from the Instances menu
• Actions > Instance Settings > Attach to Auto Scaling Group
• Select the new Auto Scaling group
• Attach your group to the instance
• If needed, edit the selected instance
• Once this is done, the instance can be added to the new Auto Scaling group.