AWS questions and answers, helpful for AWS practitioner certification and Interviews, part 2

 To watch in Youtube: click this youtube link

1.      What is elasticity in cloud computing ?

This is the strength of AWS to scale the computing resources up and down as required or as per demand. 

 

2.      What is auto scaling ?

Auto Scaling is an automatic process of connecting or removing(terminating) instances as per the load or demand .

 

3.      What is the tool in AWS for data warehousing ?

AWS Redshift

 

4.      What is the notification service in AWS cloud for alerts, alarm or notificaiton?

AWS SNS (Simple Notification Service).

 

5.      What is EBS ?

EBS stands for Elastic Block Storage. It is a storage associated with EC2 instance.

 

6.      What is EFS ?

It is Amazon Elastic File System. It is elastic, it becomes bigger or smaller according to whether you add or remove files in it. It is serverless and automatic file system, it does not require management or provisioning. This can be shared with multiple EC2 instances.

 

7.      What is ELB ?

It is Elastic Load Balancer. It automatically distributes the incoming traffic to multiple instances or servers or containers. It also monitors the health status of the instances and if it finds any instance or the target unhealthy, then it reroutes the load to other healthy instances or targets.

 

8.      Which IAM utility you should use if you need temporary access or authorization to any AWS service?

IAM Role

 

9.      You have to migrate your database to AWS, which service will you use ?

AWS Database Migration Service (AWS DMS)

 

10.   Which AWS service lets you create a private virtual cloud in the AWS ?

VPC (Virtual Private Cloud)

 

11.   To provide low-latency delivery, which AWS component does a cloud front use?

EDGE locations

 

12.   What is availability ?

Availability is the ability to remain available, to remain always functional or accessible, with no or negligible downtime.

 

13.   What is reliability ?

Ability of the cloud service to manage the resources required to meet the load or demand, to perform its intended function as well as its ability to recover if any disruption happens.

 

14.    What is elastic load balancer or elastic load balancing ?

ELB distributes the incoming traffic or load to multiple targets or instances.

 

15.   Who is responsible for managing IAM(AWS identity and access management )

The Customer

 

16.   What are AWS IAM identities ?

User

Group

Role

 

17.   What is AWS regions?

They are the major data centers placed at different locations in the world. Each region has multiple availability zones. Each availability zones has one or more discrete data centers.

 

18.   What are the different ways to create and manage AWS resources ?

AWS management console

AWS CLI(Command Line Interface)

AWS SDK(Software Development Kits)

 

19.   Which AWS service will help you monitor the EC2 instance CPU usage ?

AWS cloudwatch

 

20.   What is the principle of least privilege ?

Granting the required amount of permission to perform the required task.

 

21.   What is Aamzon Glacier ?

Amazon S3 Glacier is a data archive and data back up service. This is used to store data for long term like months, years or even more than that.

 

22.   What is AWS Cloudwatch ?

This service monitors the performance and utilization the aws services, applications and resources. It provides logs, metrics. You can set alarm or notification for utilization of the resources or when the cost goes high. So, it can monitor cost also.

 

23.   What is DNS ?

DNS stands for Domain Naming System. It is a  service to convert a domain name to IP address. Such as example.com to xx.xxx.x.xx  

 

24.   What is Route 53 ?

Route 53 is a DNS service in AWS.

 

25.   What is AWS cost explorer ?

This tool helps you view and analyze your cost for using aws services. You can view the cost for the past certain duration( such as cost for the last 6 months) or you can forecast your future cost(such as for 6 months in future) .

 

26.   What is AWS budget ?

This is another tool to monitor and control your AWS cost. With budget, you can create a plan for your spending over the period and you can set an alarm if the cost reaches that limit or exceeds that limit.

 

27.   What is spot instance ?
Spot instances uses spare or unused EC2 capacity in AWS cloud. You can get a big discuount in spot instance, upto 90%, because you can use this instance when it is available. You can run those applications which can be interrupted or if you have the flexibility to run the application at any available time.

 

28.   What are AWS Regional Services?

The scope of the service is within the region only.

VPC, ELB,ECS, DynamoDB, EC2, EFS, CloudTrail, CloudWatch, LAMDA, ELB

 

29.   What are AWS Global Services ?

The scope of the service is global.

IAM, Route53, CloudFront, S3.

 

30. What are horizontal and vertical scaling in AWS?

Horizontal scaling(also called Scaling OUT) means adding more EC2 instances, the instances share the work load.

Vertical scaling(also called Scaling UP) means you increase the compute power by adding CPU, RAM to the existing machines to manage the work load.

AWS cloud interview questions and answers, part 3

To watch in Youtube, click this link :  AWS Cloud Interview Questions and Answers, Part 3

1. What is AWS EC2 instance ?

EC2 stands for Elastic Compute Cloud. It is an AWS compute service. It is a virtual server in the AWS cloud. Customer can run their application in this server using the AWS resources. Customer can rent it when needed and remove when not needed. And you pay for the amount of time you used it. You can increase the number of instances or decrease the number as per your need. Normally, adding and removing of the instances happens automatically with AWS auto scaling. There are various different kinds of EC2 instances depending on the customers’s need. Depending on the nature of the work loads a customer can choose CPU, memory/storage, networking and other resources for the instance.

2. What is VPC ?

VPC stands for Virtual Private Cloud. It is a cloud established by an enterprise on a public cloud environment. It is a private and secure cloud environment, it is isolated from other public access and the customer can run their code, host websites, store their data and control the resources. Inside VPC the resources are connected through private subnet. The outside world connects to the application in VPC through public subnet.

3. How many subnets can be created in a VPC ?

We can create any number of subnets in a VPC. But as the number goes up the complexity also goes up, so fewer number is recommended.
 

4. How do you upgrade or downgrade a service or system with zero(near zero) downtime?

The system should always be available. If you stop and start a new instance, that will cause downtime. So, to achieve zero downtime, lunch another instance, bigger in size, install the application and all the dependencies, test the new instance, deploy the new instance and replace the old one.


5. What are the ways or tools to access AWS resources?

AWS Management Console
AWS CLI (AWS Command Line)
AWS SDK (AWS Software Development Kit)
Putty

 

6. What is DDOS?

It is distributed denial of service. DDOS attack is a cyber attack in which the attacker controls the resources. They make the server, resources, network, and application unavailable to the intended user. Normally they send multiple requests to the web server with the intention of exceeding the web server’s capacity to handle them or they might send malicious data.

The tools to handle or minimize the DDOS attack are AWS Shield, AWS WAF(Web Application Firewall) etc.

 

7. If your service is not available in the cloud in that region, what is the solution ?

Cloud does not have all the services in all the regions. Even if you compare two regions within the US, you might find the difference in the number of services. Cloud provides the services in a region according to the demand.

So, if a particular service is not available in your region, then the solution is , you choose the nearest cloud region which has that service.

 

8. What is the authorization service in AWS ?

It is AWS identity and access management service(IAM). This is an AWS services to control, through authorization and authentication, the access to the AWS services by other persons or applications.  IAM controls their access to the AWS resources to  view, create, edit or delete the resources. It ensures that the right user has the appropriate access to the right resources.

9. What are IAM identities ?

IAM identities are created to control the access to the AWS resources by persons or applications/processes. The IAM identities are Users, Groups and Roles.

Root User: This the primary account which is created when the user creates a first AWS account using his credentials such as email and password. This user has the complete access to all the services and resources in the AWS account.

IAM user: This could be a person or an application. This has the required level of permission to the necessary resources. IAM users have long term access to the resources.

IAM groups: This is a group of users, so whatever access the group has, the members of the groups automatically have those accesses. So, if you need to give permission to a large number of users, you give permission to the group in which the users are connected.

IAM roles: It is similar to the IAM users. In this the permission is given temporarily.

10. What is AWS trusted advisor ?

It is an AWS tool which helps you provision your resources according to the AWS best practices. It gives you recommendation to improve your AWS environment, to save your cost, improve performance, availability and security.

AWS Cloud Interview Questions and Answers, Part 1

 To watch in YOUTUBE: click here

1.      What is cloud computing?
It is a process to use online resources as per your need. You can increase or decrease the use of the resources as per your need or demand. This is called scalability in cloud computing.

The cloud is a collection of infrastructures of networking, database, servers, and other IT things. These are located in different regions worldwide and provide all the IT services with high reliability, availability, backup, security, lowest latency, and lowest cost.

 

2.      What are the three basic types of cloud services?

a.      Compute (AWS products: EC2, Lamda, Auto Scaling, Lightsail, Elastic BeanStalk)

b.      Storage(AWS products: S3, EBS-Elastic Block Storage, EFS-Elastic File System, Glacier)

c.      Networking(AWS Products: VPC, Route53, CloudFront)

3.      What is AWS Region?

It is a geographical area where AWS has its data centers. AWS regions are isolated from each other and they are located in various geographical locations(continents, countries) in the world.

 

4.      What are availability zones?

The availability zones (AZ) are the structures with one or more data centers. Each cloud regions have multiple availability zones. The AZs are isolated from each other. They are located in close proximity. They are designed in such a way that when one AZ is down, then another AZ backs it up and maintains continuous service.

 

5.      What is auto-scaling?

Auto-scaling provides automatic activation(provisioning and launching) of the instances according to the load or demand. The resources are automatically increased or decreased as per the demand.

 

6.      What is load balancing or elastic load balancer?

Elastic Load Balancer divides and diverts the load to multiple instances. It distributes the incoming traffic and informs if the server is overloaded or if any instance is unhealthy. If it finds any unhealthy instances, it automatically reroutes the traffic to other healthy instances. There are three types of elastic load balancers:

Application load balancer

Network load balancer

Classic load balancer

 

7.       What is cloud front?

Cloudfront is also called Content Delivery Network(CDN) service. It provides services to customers with low latency where ever the customer is located. It caches the contents and delivers the data, applications, videos, files, etc securely, quickly, and reliably.

 

8.      What is Edge Location?

These are repeater stations placed mainly in the major cities in the world to minimize the delay of response for requests from anywhere in the world. This provides a response with the lowest possible latency with the help of AWS CloudFront. Edge Location uses caching of the resources to provide service to the customer with low latency. It uses the repeater stations placed at a different location, mainly in the major cities, and provides service to the customer from the nearest repeater station.

 

9.   What is AWS cloud trail?

This is an AWS service. This monitors and tracks the activities in the cloud environment and provides the history. The activities could be adding or terminating instances, how many API calls were made, and when, in the AWS environment. Activities done by different users,  roles, or AWS services, who took the action and what action was taken and when was the action taken.  The activities are recorded as events.

This provides the logs as well as sends notifications via AWS SNS(Amazon Simple Notification Service).

This will help you analyze, and control your system as well as security analysis and take action for any potential risks.

 

10. What is AWS Cloudwatch ?

AWS CloudWatch monitors the performance and utilization of the application and resources(EC2 instances,RDS DB instances, Elastic Block Storage(EBS), Elastic Load Balancing(ELB) etc. It monitors their health status. It produces the metrics, logs and set alarms if the utilization reaches the thresholds, provides notification with SNS(Simple Notification Service). It basically monitors operational issues. It also monitors the cost of using the services and provides billing alarm if the cost goes high unexpectedly or reaches the threshold. This way you can control the AWS cost.