FRESHERS INTERVIEW Q&A
1. Define and explain the three basic types of cloud services and the AWS products that are built based on them?
The three basic types of cloud services are:
• Computing
• Storage
• Networking
Here are some of the AWS products that are built based on the three cloud service types:
Computing – These include EC2, Elastic Beanstalk, Lambda, Auto-Scaling, and Lightsat.
Storage – These include S3, Glacier, Elastic Block Storage, Elastic File System.
Networking – These include VPC, Amazon CloudFront, Route53
2. What is auto-scaling?
Auto-scaling is a function that allows you to provision and launch new instances whenever there is a demand. It allows you to automatically increase or decrease resource capacity in relation to the demand.
3. What is geo-targeting in CloudFront?
Geo-Targeting is a concept where businesses can show personalized content to their audience based on their geographic location without changing the URL. This helps you create customized content for the audience of a specific geographical area, keeping their needs in the forefront.
4. How do you upgrade or downgrade a system with near-zero downtime?
You can upgrade or downgrade a system with near-zero downtime using the following steps of migration:
• Open EC2 console
• Choose Operating System AMI
• Launch an instance with the new instance type
• Install all the updates
• Install applications
• Test the instance to see if it’s working
• If working, deploy the new instance and replace the older instance
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?
You can know that you are paying the correct amount for the resources that you are using by employing the following resources:
Check the Top Services Table
It is a dashboard in the cost management console that shows you the top five most used services. This will let you know how much money you are spending on the resources in question.
Cost Explorer
There are cost explorer services available that will help you to view and analyze your usage costs for the last 13 months. You can also get a cost forecast for the upcoming three months.
AWS Budgets
This allows you to plan a budget for the services. Also, it will enable you to check if the current plan meets your budget and the details of how you use the services.
Cost Allocation Tags
This helps in identifying the resource that has cost more in a particular month. It lets you organize your resources and cost allocation tags to keep track of your AWS costs.
6. Is there any other alternative tool to log into the cloud environment other than console?
• Putty
• AWS CLI for Linux
• AWS CLI for Windows
• AWS CLI for Windows CMD
• AWS SDK
• Eclipse
7. What services can be used to create a centralized logging solution?
The essential services that you can use are Amazon CloudWatch Logs, store them in Amazon S3, and then use Amazon Elastic Search to visualize them. You can use Amazon Kinesis Firehose to move the data from Amazon S3 to Amazon Elastic Search.
8. What is a DDoS attack, and what services can minimize them?
DDoS is a cyber-attack in which the perpetrator accesses a website and creates multiple sessions so that the other legitimate users cannot access the service. The native tools that can help you deny the DDoS attacks on your AWS services are:
• AWS Shield
• AWS WAF
• Amazon Route53
• Amazon CloudFront
• ELB
• VPC
9. How do you set up a system to monitor website metrics in real-time in AWS?
Amazon CloudWatch helps you to monitor the application status of various AWS services and custom events. It helps you to monitor:
• State changes in Amazon EC2
• Auto-scaling lifecycle events
• Scheduled events
• AWS API calls
• Console sign-in events
10. What are the different types of virtualization in AWS, and what are the differences between them?
The three major types of virtualization in AWS are:
Hardware Virtual Machine (HVM)
It is a fully virtualized hardware, where all the virtual machines act separate from each other. These virtual machines boot by executing a master boot record in the root block device of your image.
Paravirtualization (PV)
Paravirtualization-GRUB is the bootloader that boots the PV AMIs. The PV-GRUB chain loads the kernel specified in the menu.
Paravirtualization on HVM
PV on HVM helps operating systems take advantage of storage and network I/O available through the host.
11. Name some of the AWS services that are not region-specific
AWS services that are not region-specific are:
• IAM
• Route 53
• Web Application Firewall
• CloudFront
12. What is CloudWatch?
The Amazon CloudWatch has the following features:
Depending on multiple metrics, it participates in triggering alarms.
Helps in monitoring the AWS environments like CPU utilization, EC2, Amazon RDS instances, Amazon SQS, S3, Load Balancer, SNS, etc.
13. What is an Elastic Transcoder?
To support multiple devices with various resolutions like laptops, tablets, and smartphones, we need to change the resolution and format of the video. This can be done easily by an AWS Service tool called the Elastic Transcoder, which is a media transcoding in the cloud that exactly lets us do the needful. It is easy to use, cost-effective, and highly scalable for businesses and developers.
14. Define Amazon EC2 regions and availability zones?
Availability zones are geographically separate locations. As a result, failure in one zone has no effect on EC2 instances in other zones. When it comes to regions, they may have one or more availability zones. This configuration also helps to reduce latency and costs.
15. Explain Amazon EC2 root device volume?
The image that will be used to boot an EC2 instance is stored on the root device drive. This occurs when an Amazon AMI runs a new EC2 instance. And this root device volume is supported by EBS or an instance store. In general, the root device data on Amazon EBS is not affected by the lifespan of an EC2 instance.