Mounting an EBS Volume on a Linux EC2 Instance in AWS (Amazon Web Services)

Mounting an EBS Volume on a Linux EC2 Instance in AWS (Amazon Web Services)

In this article,we will see Mounting an EBS Volume on a Linux EC2 Instance.

Implementation Steps

1. View your existing Instance.
2. Connect to Linux EC2 Instance through putty.
3. Mount an EBS Volume to your Linux EC2 Instance.

First, we need to AWS Console page by using below link.

https://aws.amazon.com/console/

Click on sign in to Console button.

Logging to aws account

Login using username & password and click on sign in.

Enter to AWS Management Console

We can see the AWS Management Console Dashboard.

Go to Services, under the compute module click EC2 service to open.

I have already launched Instance.

View your existing Instance

We can see Linux Server “My Linux” which was created earlier.

Verify volumes of your Linux EC2 Instance.

Go volumes,we can see two volumes attached to Linux EC2 Instance.

The first one is root volume and second one is EBS volume.

Note

If you want to store the files inside the EBS volume, you need to mount EBS volume to your Linux EC2 Instance.Manually.

Connect to Linux EC2 Instance through putty

Mount an EBS Volume to your Linux EC2 Instance.

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login as: ec2-user   Authenticating with public key "imported-openssh-key"   Last login: Wed Nov 27 10:17:56 2019 from 123.201.77.64          __|  __|_  )          _|  (     /   Amazon Linux 2 AMI         ___|\___|___|   https://aws.amazon.com/amazon-linux-2/   5 package(s) needed for security, out of 13 available   Run "sudo yum update" to apply all updates.   [ec2-user@ip-172-31-34-108 ~]$

Switch to root user

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[ec2-user@ip-172-31-34-108 ~]$ sudo su   [root@ip-172-31-34-108 ec2-user]#

Verify Available disks in your Linux Server

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[root@ip-172-31-34-108 ec2-user]# lsblk   NAME    MAJ:MIN RM SIZE RO TYPE MOUNTPOINT   xvda    202:0    0   8G  0 disk   └─xvda1 202:1    0   8G  0 part /   xvdb    202:16   0  10G  0 disk

Verify the volume has any data by using the following command.

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[root@ip-172-31-34-108 ec2-user]#file -s /dev/xvdb   data

Format the volume to ext4 filesystem

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[root@ip-172-31-34-108 ec2-user]# mkfs -t ext4 /dev/xvdb   mke2fs 1.42.9 (28-Dec-2013)   Filesystem label=   OS type: Linux   Block size=4096 (log=2)   Fragment size=4096 (log=2)   Stride=0 blocks, Stripe width=0 blocks   655360 inodes, 2621440 blocks   131072 blocks (5.00%) reserved for the super user   First data block=0   Maximum filesystem blocks=2151677952   80 block groups   32768 blocks per group, 32768 fragments per group   8192 inodes per group   Superblock backups stored on blocks:           32768, 98304, 163840, 229376, 294912, 819200, 884736, 1605632   Allocating group tables: done   Writing inode tables: done   Creating journal (32768 blocks): done   Writing superblocks and filesystem accounting information: done

Create a directory to mount our new ext4 volume (use any directory name you like)

Make Directory

1 2	[root@ip-172-31-34-108 ec2-user]# mkdir /ktexperts

Mount the volume to “ktexperts” directory

1 2	[root@ip-172-31-34-108 ec2-user]# mount /dev/xvdb /ktexperts

Verify the disk space in your Linux Server

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[root@ip-172-31-34-108 ec2-user]# df -h   Filesystem      Size  Used Avail Use% Mounted on   devtmpfs        475M     0  475M   0% /dev   tmpfs           492M     0  492M   0% /dev/shm   tmpfs           492M  404K  492M   1% /run   tmpfs           492M     0  492M   0% /sys/fs/cgroup   /dev/xvda1      8.0G  1.3G  6.8G  16% /   tmpfs            99M     0   99M   0% /run/user/1000   /dev/xvdb       9.8G   37M  9.2G   1% /ktexperts

Go to Mount Directory and verify files.

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[root@ip-172-31-34-108 ec2-user]# cd /ktexperts/   [root@ip-172-31-34-108 ktexperts]# ls -l   total 16   drwx------ 2 root root 16384 Nov 27 10:25 lost+found   [root@ip-172-31-34-108 ktexperts]#

Make Files and Directories inside mount directory

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[root@ip-172-31-34-108 ktexperts]# ls   aws  ktexpers1  ktexperts2  ktexperts3  ktexperts4  lost+found   [root@ip-172-31-34-108 ktexperts]# touch ktexpers1 ktexperts2 ktexperts3 ktexperts4   [root@ip-172-31-34-108 ktexperts]# ls   ktexpers1  ktexperts2  ktexperts3  ktexperts4  lost+found   [root@ip-172-31-34-108 ktexperts]# mkdir aws   [root@ip-172-31-34-108 ktexperts]# ls   ktexpers1  ktexperts2  ktexperts3  ktexperts4  lost+found   aws

EBS Automount on Reboot

By default on every reboot the  EBS volumes other than root volume will get unmounted.

To enable automount, you need to make an entry in the /etc/fstab file

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[root@ip-172-31-34-108 ktexperts]# vi /etc/fstab   Enter the below command inside the fstab file   /dev/xvdf       /newvolume   ext4    defaults,nofail        0       0

Execute the following command to check id the fstab file has any error

1 2	[root@ip-172-31-34-108 ktexperts]# sudo mount -a

Thank you for giving your valuable time to read the above information.

Top 50 AWS Interview Questions and Answers

Top 50 AWS Interview Questions and Answers


Compare AWS with OpenStack
Services

AWS

OpenStack

User Interface

GUI-Console

API-EC2 API

CLI -Available

GUI-Console

API-EC2 API

CLI -Available

Computation

EC2

Nova

File Storage

S3

Swift

Block Storage

EBS

Cinder

Networking

IP addressing Egress, Load Balancing Firewall (DNS) , VPC

IP addressing load balancing firewall (DNS)

Big Data

Elastic MapReduce

-

What type of performance can you expect from Elastic Block Storage? How do you back it up and enhance the performance ?
Performance of an elastic block storage varies i.e. it can go above the SLA performance level and after that drop below it. SLA provides an average disk I/O rate  which can at times frustrate performance experts who yearn for reliable and consistent disk throughput on a server. Virtual AWS instances do not behave this way. One can backup EBS volumes through a graphical user interface like elasticfox or use the snapshot facility through an API call. Also, the performance can be improved by using Linux software raid and striping across four volumes.

Imagine that you have an AWS application that requires 24x7 availability and can be down only for a maximum of 15 minutes. How will you ensure that the database hosted on your EBS volume is backed up?
Automated backup are the key processes here as they work in the background without requiring any manual intervention. Whenever there is a need to back up the data, AWS API and AWS CLI play a vital role in automating the process through scripts. The best way is to prepare for a timely backup of EBS of the EC2 instance. The EBS snapshot should be stored on Amazon S3 and can be used for recovery of the database instance in case of any failure or downtime.

You create a Route 53 latency record set from your domain to a system in Singapore and a similar record to a machine in Oregon. When a user located in India visits your domain, to which location will he be routed to?
Assuming that the application is hosted on Amazon EC2 instance and multiple instances of the applications are deployed on different EC2 regions. The request is most likely to go to Singapore because Amazon Route 53 is based on latency and it routes the requests based on the location that is likely to give the fastest response possible.

Differentiate between on-demand instance and spot instance.
Spot Instances  are spare unused EC2 instances which one can bid for. Once the bid exceeds the existing spot price (which changes in real-time based on demand and supply) the spot instance will be launched. If the spot price becomes more than the bid price then the instance can go away anytime and terminated within 2 minutes of notice. The best way to decide on the optimal bid price for a spot instance is to check the price history of last 90 days that is available on AWS console. The advantage of spot instances is that they are cost-effective and the drawback is that they can be terminated anytime. Spot instances are ideal to use when –

There are optional nice to have tasks.
You have flexible workloads which can be run when there is enough compute capacity.
Tasks that require extra computing capacity to improve performance.
On-demand instances are made available whenever you require them and you need to pay for the time you use them on an hourly basis. These instances can be released when they are no longer required and do not require any upfront commitment. The availability fo these instances is guaranteed by AWS unlike spot instances.

The best practice is to launch couple of on-demand instances which can maintain minimum level of guaranteed compute resources for the application and add-on few spot instances whenever there is an opportunity.

 How will you access the data on EBS in AWS ?
Elastic block storage as the name indicates provides persistent, highly avaialble and high performance block level storage that can be attached to a running EC2 instance. The storage can formatted and mounted as a file system or the raw storage can be accessed directly.

 What is the boot time for an instance store backed instance ?
The boot time for an Amazon Instance Store -Backed AMI is usually less than 5 minutes.

Is it possible to vertically scale on an Amazon Instance?  If yes, how ?
Following are the steps to scale an Amazon Instance vertically –

Spin up a larger Amazon instance than the existing one.
Pause the exisiting instance to remove the root ebs volume from the server  and discard.
Stop the live running instance and detach its root volume.
Make a note of the unique device ID and attach that root volume to the new server.
Start the instance again.
 Differentiate between vertical and horizontal scaling in AWS.
The main difference between vertical and horizontal scaling is the way in which you add compute resources to your infrastructure. In vertical scaling, more power is added to the existing machine while in horizontal scaling additional resources are added into the system with the addition of more machines into the network so that the workload and processing is shared among multiple devices. The best way to understand the difference is imagine that you are retiring your Toyota and buying a Ferrari because you need more horsepower. This is vertical scaling. Another way to get that added horsepower is not to ditch the Toyota for the Ferrari but buy another car. This can be related to horizontal scaling where you drive several cars all at once.

When the users are up to 100, an EC2 instance alone is enough to run the entire web application or the database until the traffic ramps up. Under such circumstances when the traffic ramps up, it is better to scale vertically by increasing the capacity of the EC2 instance to meet the increasing demands of the application. AWS supports instances up to 128 virtual cores or 488GB RAM.

When the users for your application grow up to 1000 or more, vertical cannot handle requests and there is need for horizontal scaling which is achieved through distributed file system, clustering, and load balancing.

What is the total number of buckets that can be created in AWS by default ?
100 buckets can be created in each of the AWS accounts. If additional buckets are required, increase the bucket limit by submitting a service limit increase.

Differentiate between Amazon RDS, Redshift and Dynamo DB.


Features

Amazon RDS

Redshift

Dynamo DB

Computing Resources

Instances with 64 vCPU and 244 GB RAM



Nodes with vCPU and 244 GB RAM

Not specified, SaaS-Software as a Service.

Maintenance Window

30 minutes every week.

30 minutes every week.

No impact

Database Engine

MySQL, Oracle DB, SQL Server,Amazon Aurora, Postgre SQL

Redshift

NoSQL

Primary Usage Feature

Conventional Databases

Datawarehouse

Database for dynamically modified data

Multi A-Z Replication

Additional Service

Manual

In-built



An organization wants to deploy a two-tier web applications on AWS.  The application requires complex query processing and table joins. However, the company has limited resources and requires high availability. Which is the best configuration that company can opt for based on the requirements ?
DynamoDB deals with core problems of database scalability, management, reliability, and performance but does not have the functionalities of a RDBMS. DynamoDB does not render support for complex joins or query processing or complex transactions.  You can run a relational engine on Amazon RDS or EC2 for this kind of a functionality.

 If you have half of the workload on public cloud while the other half is on local storage, what kind of architecture will you use for this ?
Hybrid Cloud Architecture

 Is it possible to cast-off S3 with EC2 instances ? If yes, how ?
It is possible to cast-off S3 with EC2 instances using root approaches backed by native occurrence storage.

  How will you configure an instance with the application and its dependencies , and make it ready to serve traffic?
You can acheive this with the use of lifecycle hooks. They are powerful as they let you pause the creation or termination of an instance so that you can sneak peak in and perform custom actions like configuring the instance, downloading the required files, and any other steps that are required to make the instance ready.Every auto scaling group can have multiple lifecycle hooks.

 How can you safeguard EC2 instances running on a VPC ?
AWS Security groups associated with EC2 instances can help you safeguard EC2 instances running in a VPC by providing security at the protocol and port access level. You can configure both INBOUND and OUTBOUND traffic to enables secured access for the EC2 instance.AWS security groups are much similar to a firewall-they contain set of rules which filter the traffic coming into and out of an EC2 instance and deny any kind of unauthorized access to EC2 instances.

How many EC2 instances can be used in a VPC ?
There is a limit of running up to a total of 20 on-demand instances across the instance family , you can purchase 20 reserved instances and request spot instances as per your dynamic spot limit region.

What are some of the key best practices for security in Amazon EC2?
Create individual IAM (Identity and Access Management) users to control access to your AWS recourses. Creating separate IAM user provides separate credentials for every user making it possible to assign different permissions to each user based on the access requirements.
Secure the AWS Root account and its access keys.
Harden EC2  instances by disabling unnecessary services and applications by installing only necessary software and tools on EC2 instances.
Grant least privileges by opening up permissions that are required to perform a specific task and not more than that. Additional permissions can be granted as required.
Define and review the security group rules on a regular basis.
Have a well-defined strong password policy for all the users.
Deploy anti-virus software on the AWS network to protect it from Trojans, Viruses, etc.
What should be the instance’s tenancy attribute for running it on a single tenant hardware ?
The instance tenancy attribute must be set to a dedicated instance and other values might not be appropriate for this operation.

There is a distributed application that processes huge amounts of data across various EC2 instances.  Application is designed in such a way that it can recover gracefully from EC2 instance failures. How will you accomplish this in a cost effective manner ?
On-demand or reserved instance will not be ideal in this case as the task here is not continuous. Moreover. It does not make sense to launch an on-demand instance whenever work comes up because on-demand instances are expensive.In this case, the ideal choice would be to opt for a spot instance owing to its cost effectiveness and no long term commitments.

 What are the important features of a classic load balancer in EC2 ?
The high availability feature ensures that the traffic is distributed among EC2 instances in single or multiple availability zones.This ensures high scale of availability for incoming traffic.
Classic load balancer can decide whether to route the traffic or not based on the results of health check.
You can implement secure load balancing within a network  by creating security groups in a VPC.
Classic load balancer supports sticky sessions which ensure that the traffic from a user is always routed to the same instance for a seamless experience.
What parameters will you take into consideration when choosing the availability zone ?
Performance, pricing, latency, and response time are some of the factors to consider when selecting the availability zone.

 Which instance will you use for deploying a 4-node Hadoop cluster in AWS ?
We can use a c4.8x large instance or i2.large for this, but using a c4.8x will require a better configuration on PC.

 Will you use encryption for S3 ?
It is better to consider encryption for sensitive data on S3 as it is a proprietary technology.

How can you send request to Amazon S3 ?
Using the REST API or the AWS SDK wrapper libraries which wrap the underlying Amazon S3 REST API.

How will you bind the user session with a specific instance in ELB (Elastic Load Balancer) ?
This can be achieved by enabling Sticky Session.

 What are the possible connection issues you encounter when connecting to an EC2 instance ?
Unprotected private key file
Server refused key
Connection timed out
No supported authentication method available
Host key not found,permission denied.
User key not recognized by the server, permission denied.
What is the difference between Amazon S3 and EBS ?


Amazon S3

EBS

Paradigm

Object Store

Filesystem

Security

Private Key or Public Key

Visible only to your EC2

Redundancy

Across data centers

Within the data center

Performance

Fast

Superfast



Can you run multiple websites on an EC2 server using a single IP address?
More than one elastic IP is required to run multiple websites on EC2.

What happens when you reboot an EC2 instance?
Rebooting an instance is just similar to rebooting a PC. You do not return to image’s original state, however, the contents of the hard disk are same as before the reboot.

A content management system running on EC2 instance is approaching 100% CPU utilization. How will you reduce the load on EC2 instance ?
This can be done by attaching a load balancer to an autoscaling group to efficiently distribute load among all instances.

What happens when you launch instances in Amazon VPC ?
Each instance has a default IP address when the instance is launched in Amazon VPC. This approach is considered ideal when you need to connect cloud resources with the data centers.

Can you modify the private IP address of an EC2 instance while it is running in a VPC ?
It is not possible to change the primary private IP addresses. However, secondary IP addresses can be assigned, unassigned or moved between instances at any given point.

 You are launching an instance under the free usage tier from AMI having a snapshot size of 50GB. How will you launch the instance under the free usage tier ?
It is not possible to launch this instance under the free usage tier.

Which load balancer will you use to make routing decisions at the application layer or transport layer that  supports either VPC or EC2?
Classic Load Balancer

Scenario-Based AWS Architect Interview Questions
You have a webserver on EC2 instance . Your instance can get to the web but nobody on the internet can get to your webserver. How will you troubleshoot this issue ?
What steps will you perform to enable a server in private subnet of a VPC to download updates from the web?
How will you build a self-healing AWS architecture ?
How will you design an AWS architecture for failure ?
As a AWS solution architect, how will you implement disaster recovery on AWS ?
You run a news website in eu-west-1 region which updates every 15 minutes. The website is accessed by audience across the globe and uses an auto scaling group begind an Elastic load balancer and Amazon relation database service. Static content for the application is on S3 and is distributed using CloudFront. The auto scaling group is set to trigger a scale up event with 60% CPU utilization. You use extra large DB instance with 10.000 Provisioned IOPS that gives CPU Utilization around 80% with freeable memory in the 2GB range. The web analytics report shows that the load time for the webpages is an average of 2 seconds but the SEO consultant suggests that you bring the average load time of your pages to less than 0.5 seconds. What will you do improve the page load time of the website for your users.
How will you right size a system for a normal and peak traffic situations ?
Tell us about a situation where you were given feedback that made you change your architectural design strategy.
What challenges are you looking forward to for the position as an AWS solutions architect ?
 Describe a successful AWS project which reflects your design and implementation experience about AWS Solutions Architecture.
 How will you design an e-commerce application using AWS services ?
What characteristics will you take into consideration when desgining an Amazon Cloud solution?
When would you prefer to use provisioned IOPS over Standard RDS storage ?
What do you think AWS is missing from a solutions architect perspective?
What if Google decides to host YouTube.com on AWS, how will you design the solution architecture ?

Top Amazon AWS Interview Questions – Most Asked

If you are going for an AWS interview, then this experts-prepared list of AWS interview questions is all you need to get through it. Additionally, AWS Course will help you gain expertise in cloud architecture, starting, stopping, and terminating an AWS instance, comparing between Amazon Machine Image and an instance, auto-scaling, vertical scalability, AWS security, and more. This exclusive set of AWS interview questions is designed for all the professionals who are interested to learn about Cloud Computing, and it will help you in your career, aimed at pursuing various cloud job profiles like AWS Solution Architect, AWS Engineer, DevOps Engineer, Cloud Architect, etc.



Top Answers to AWS Interview Questions
1. Compare between AWS and OpenStack.
Criteria AWS OpenStack
License Amazon proprietary Open source
Operating system Whatever the cloud administrator provides Whatever AMIs provided by AWS
Performing repeatable operations Through templates Through text files
2. What is AWS?
AWS (Amazon Web Services) is a platform to provide secure cloud services, database storage, offerings to compute power, content delivery, and other services to help business level and develop.

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3. What is the importance of buffer in Amazon Web Services?
An Elastic Load Balancer ensures that the incoming traffic is distributed optimally across various AWS instances.  A buffer will synchronize different components and makes the arrangement additionally elastic to a burst of load or traffic. The components are prone to work in an unstable way of receiving and processing requests. The buffer creates an equilibrium linking various apparatus and crafts them work at an identical rate to supply more rapid services.

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4. How are Spot Instance, On-demand Instance, and Reserved Instance different from one another?
Both Spot Instance and On-demand Instance are models for pricing.

Spot Instance On-demand Instance
With Spot Instance, customers can purchase compute capacity with no upfront commitment at all. With On-demand Instance, users can launch instances at any time based on the demand.
Spot Instances are spare Amazon instances that you can bid for. On-demand Instances are suitable for high-availability needs of applications.
When the bidding price exceeds the spot price, the instance is automatically launched, and the spot price fluctuates based on supply and demand for instances. On-demand Instances are launched by users only with the pay-as-you-go model.
When the bidding price is less than the spot price, the instance is immediately taken away by Amazon. On-demand Instances will remain persistent without any automatic termination from Amazon.
Spot Instances are charged on an hourly basis. On-demand Instances are charged on a per-second basis


5. Your organization has decided to have all their workload on the public cloud. But, due to certain security concerns, your organization decides to distribute some of the workload on private servers. You are asked to suggest a cloud architecture for your organization. What will be your suggestion?
A hybrid cloud. The hybrid cloud architecture is where an organization can use the public cloud for shared resources and the private cloud for its confidential workloads.

6. The data on the root volumes of store-backed and EBS-backed instances get deleted by default when they are terminated. If you want to prevent that from happening, which instance would you use?
EBS-backed instances. EBS-backed instances use EBS volume as their root volume. EBS volume consists of virtual drives that can be easily backed up and duplicated by snapshots. The biggest advantage of EBS-backed volumes is that the data can be configured to be stored for later retrieval even if the virtual machine or the instances are shut down.

7. Which one of the storage solutions offered by AWS would you use if you need extremely low pricing and data archiving?
Amazon Glacier. AWS Glacier is an extremely low-cost storage service offered by Amazon that is used for data archiving and backup purposes. The longer you store data in Glacier, the lesser it will cost you.

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8. You have connected four instances to ELB. To automatically terminate your unhealthy instances and replace them with new ones, which functionality would you use?
Auto-scaling groups

9. How will you configure an Amazon S3 bucket to serve static assets for your public web application?
By configuring the bucket policy to provide public read access to all objects

10. Your organization wants to send and receive compliance emails to its clients using its own email address and domain. What service would you suggest for achieving the same in an easy and cost-effective way?
Amazon Simple Email Service (Amazon SES), which is a cloud-based email sending service, can be used for this purpose.



11. Can you launch Amazon Elastic Compute Cloud (EC2) instances with predetermined private IP addresses? If yes, then with which Amazon service it is possible?
Yes. It is possible by using VPC (Virtual Private Cloud).

12. Why do we make subnets?
Creating subnets means dividing a large network into smaller ones. These subnets can be created for several reasons. For example, creating and using subnets can help reduce congestion by making sure that the traffic destined for a subnet stays in that subnet. This helps in efficiently routing the traffic coming to the network that reduces the network’s load.

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13. If you launched a standby RDS, will it be launched in the same availability zone as your primary?
No, standby instances are automatically launched in different availability zones than the primary, making them physically independent infrastructures. This is because the whole purpose of standby instances is to prevent infrastructure failure. So, in case the primary goes down, the standby instance will help recover all of the data.

14. Which of the following is a global Content Delivery Network service that securely delivers data to users with low latency and high transfer speed.
Amazon CloudFront

15. Which Amazon solution will you use if you want to accelerate moving petabytes of data in and out of AWS, using storage devices that are designed to be secure for data transfer?
Amazon Snowball. AWS Snowball is the data transport solution for large amounts of data that need to be moved into and out of AWS using physical storage devices.

16. If you are running your DB instance as Multi-AZ deployment, can you use standby DB instances along with your primary DB instance?
No, the standby DB instance cannot be used along with the primary DB instances since the standby DB instances are supposed to be used only if the primary instance goes down.

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17. Your organization is developing a new multi-tier web application in AWS. Being a fairly new and small organization, there’s limited staff. But, the organization requires high availability. This new application comprises complex queries and table joins. Which Amazon service will be the best solution for your organization’s requirements?
DynamoDB will be the right choice here since it is designed to be highly scalable, more than RDS or any other relational database services.

18. Your organization is using DynamoDB for its application. This application collects data from its users every 10 minutes and stores it in DynamoDB. Then every day, after a particular time interval, the data (respective to each user) is extracted from DynamoDB and sent to S3. Then, the application visualizes this data to the users. You are asked to propose a solution to help optimize the backend of the application for latency at lower cost. What would you recommend?
ElastiCache. Amazon ElastiCache is a caching solution offered by Amazon. It can be used to store a cached version of the application in a region closer to users so that when requests are made by the users the cached version of the application can respond, and hence latency will be reduced.

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19. You accidently stopped an EC2 instance in a VPC with an associated Elastic IP. If you start the instance again, what will be the result?
The data stored on the instance will be lost. Elastic IP is disassociated from the instance only if the instance is terminated.

20. Your organization has around 50 IAM users. Now, it wants to introduce a new policy that will affect the access permissions of an IAM user. How can it implement this without having to apply the policy at the individual user level?
It is possible using IAM groups, by adding users in the groups as per their roles and by simply applying the policy to the groups.

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21. I created a web application with autoscaling. I observed that the traffic on my application is the highest on Wednesdays and Fridays between 9 AM and 7 PM. What would be the best solution for me to handle the scaling?
Configure a policy in autoscaling to scale as per the predictable traffic patterns.

22. How would you handle a situation where the relational database engine crashes often whenever the traffic to your RDS instances increases, given that the replica of RDS instance is not promoted as the master instance?
A bigger RDS instance type needs to be opted for handling large amounts of traffic, creating manual or automated snapshots to recover data in case the RDS instance goes down.

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23. Is there a way to upload a file that is greater than 100 megabytes in Amazon S3?
Yes, it is possible by using multipart upload utility from AWS. With multipart upload utility, larger files can be uploaded in multiple parts that are uploaded independently. You can also decrease upload time by uploading these parts in parallel. After the upload is done, the parts will be merged into a single object or file to create the original file from which the parts were created.

24. Suppose, you hosted an application on AWS that lets the users render images and do some general computing. Which of the below listed services can you use to route the incoming user traffic?
Classic Load Balancer
Application Load Balancer
Network Load balancer
Application Load Balancer: It supports path-based routing of the traffic and hence helps in enhancing the performance of the application structured as smaller services. Using application load balancer, the traffic can be routed based on the requests made. In this case scenario, the traffic where requests are made for rendering images can be directed to the servers only deployed for rendering images and the traffic where the requests are made for computing can be directed to the servers deployed only for general computing purposes.

25. You have an application running on your Amazon EC2 instance. You want to reduce the load on your instance as soon as the CPU utilization reaches 100 percent. How will you do that?
It can be done by creating an autoscaling group to deploy more instances when the CPU utilization exceeds 100 percent and distributing traffic among instances by creating a load balancer and registering the Amazon EC2 instances with it.

26. What would I have to do if I want to access Amazon Simple Storage buckets and use the information for access audits?
AWS CloudTrail can be used in this case as it is designed for logging and tracking API calls, and it has also been made available for storage solutions.

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27. I created a key in North Virginia region to encrypt my data in Oregon region. I also added three users to the key and an external AWS account. Then, to encrypt an object in S3, when I tried to use the same key, it was not listed. Where did I go wrong?
The data and the key should be in the same region. That is, the data that has to be encrypted should be in the same region as the one in which the key was created. In this case, the data is in Oregon region, whereas the key is created in North Virginia region.



28. Suppose, I created a subnet and launched an EC2 instance in the subnet with default settings. Which of the following options will be ready to use on the EC2 instance as soon as it is launched?
Elastic IP
Private IP
Public IP
Internet Gateway
Private IP. Private IP is automatically assigned to the instance as soon as it is launched. While elastic IP has to be set manually, Public IP needs an Internet Gateway which again has to be created since it’s a new VPC.

29. Your organization has four instances for production and another four for testing. You are asked to set up a group of IAM users that can only access the four production instances and not the other four testing instances. How will you achieve this?
We can achieve this by defining tags on the test and production instances and then adding a condition to the IAM policy that allows access to specific tags.

30. What is the maximum number of S3 buckets you can create?
50
20
70
100
100

31. Your organization wants to monitor the read and write IOPS for its AWS MySQL RDS instance and then send real-time alerts to its internal operations team. Which service offered by Amazon can help your organization achieve this scenario?
Amazon CloudWatch would help us achieve this. Since Amazon CloudWatch is a monitoring tool offered by Amazon, it’s the right service to use in the above-mentioned scenario.

32. Which of the following services can be used if you want to capture client connection information from your load balancer at a particular time interval?
Enabling access logs on your load balancer
Enabling CloudTrail for your load balancer
Enabling CloudWatch metrics for your load balancer
Enabling CloudTrail for your load balancer. AWS CloudTrail is an inexpensive log monitoring solution provided by Amazon. It can provide logging information for load balancer or any other AWS resources. The provided information can further be used for analysis.

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33. You have created a VPC with private and public subnets. In what kind of subnet would you launch the database servers?
Database servers should be ideally launched in private subnets. Private subnets are ideal for the backend services and databases of all applications since they are not meant to be accessed by the users of the applications, and private subnets are not routable from the Internet.

34. Is it possible to switch from an Instance-backed root volume to an EBS-backed root volume at any time?
No, it is not possible.

35. How can you save the data on root volume on an EBS-backed machine?
By overriding the terminate option

36. When should you use the classic load balancer and the application load balancer?
The classic load balancer is used for simple load balancing of traffic across multiple EC2 instances. While, the application load balancing is used for more intelligent load balancing, based on the multi-tier architecture or container-based architecture of the application. Application load balancing is mostly used when there is a need to route traffic to multiple services.

37. Can you change the instance type of the instances that are running in your application tier and are also using autoscaling? If yes, then how? (Choose one of the following)
Yes, by modifying autoscaling launch configuration
Yes, by modifying autoscaling tags configuration
Yes, by modifying autoscaling policy configuration
No, it cannot be changed
Yes, the instance type of such instances can be changed by modifying autoscaling launch configuration. The tags configuration is used to add metadata to the instances.

38. Can you name the additional network interface that can be created and attached to your Amazon EC2 instance launched in your VPC?
Elastic Network Interface

39. Out of the following options, where does the user specify the maximum number of instances with the autoscaling commands?
Autoscaling policy configuration
Autoscaling group
Autoscaling tags configuration
Autoscaling launch configuration
Autoscaling launch configuration

40. Which service provided by AWS can you use to transfer objects from your data center, when you are using Amazon CloudFront?
Amazon Direct Connect. It is a network service that acts as an alternative to using the Internet to connect customers in on-premise sites with AWS.

41. You have deployed multiple EC2 instances across multiple availability zones to run your website. You have also deployed a Multi-AZ RDS MySQL Extra Large DB Instance. The site performs a high number of small read and write operations per second. After some time, you observed that there is read contention on RDS MySQL. What would be your approach to resolve the contention and optimize your website?
We can deploy ElastiCache in memory cache running in every availability zone. This will help in creating a cached version of the website for faster access in each availability zone. We can also add RDS MySQL read replica in each availability zone that can help in efficient and better performance for read operations. So, there will not be any increased workload on RDS MySQL instance, hence resolving the contention issue.

42. Your company wants you to propose a solution so that the company’s data center can be connected to Amazon cloud network. What would be your proposal?
The data center can be connected to Amazon cloud network by establishing a virtual private network (VPN) between the VPC and the data center. Virtual private network lets you establish a secure pathway or tunnel from your premise or device to AWS global network.

43. Which of the following Amazon Services would you choose if you want complex querying capabilities but not a whole data warehouse?
RDS
Redshift
ElastiCache
DynamoDB
Amazon RDS

44. You want to modify the security group rules while it is being used by multiple EC2 instances. Will you be able to do that? If yes, will the new rules be implemented on all previously running EC2 instances that were using that security group?
Yes, the security group that is being used by multiple EC2 instances can be modified. The changes will be implemented immediately and be applied to all the previously running EC2 instances without restarting the instances



45. Which one of the following is a structured data store that supports indexing and data queries to both EC2 and S3?
DynamoDB
MySQL
Aurora
SimpleDB
SimpleDB

46. How many total VPCs per account/region and subnets per VPC can you have?
4, 100
7, 40
5, 200
3, 150
5, 200

47. Which service offered by Amazon will you choose if you want to collect and process e-commerce data for near real-time analysis? (Choose any two)
DynamoDB
Redshift
Aurora
SimpleDB
DynamoDB. DynamoDB is a fully managed NoSQL database service that can be fed any type of unstructured data. Hence, DynamoDB is the most apt choice for collecting data from e-commerce websites.

For near real-time analysis, we can use Amazon Redshift.

48. If in CloudFront the content is not present at an edge location, what will happen when a request is made for that content?
CloudFront will deliver the content directly from the origin server. It will also store the content in the cache of the edge location where the content was missing.

49. Can you change the private IP address of an EC2 instance while it is in running or in a stopped state?
No, it cannot be changed. When an EC2 instance is launched, a private IP address is assigned to that instance at the boot time. This private IP address is attached to the instance for its entire lifetime and can never be changed.

50. Which of the following options will you use if you have to move data over long distances using the Internet, from instances that are spread across countries to your Amazon S3 bucket?
Amazon CloudFront
Amazon Transfer Acceleration
Amazon Snowball
Amazon Glacier
Amazon Transfer Acceleration. It throttles the data transfer up to 300 percent using optimized network paths and Amazon Content Delivery Network. Snowball cannot be used here as this service does not support cross-region data transfer.

51. Which of the following services is a data storage system that also has REST API interface and uses secure HMAC-SHA1 authentication keys?
Amazon Elastic Block Store
Amazon Snapshot
Amazon S3
Amazon S3. It gets various requests from applications, and it has to identify which requests are to be allowed and which to be denied. Amazon S3 REST API uses a custom HTTP scheme based on a keyed HMAC for authentication of requests.

52. What kind of IP address can you use for your customer gateway (CGW) address?
We can use the Internet routable IP address, which is a public IP address of your NAT device.

If you have any doubts or queries related to AWS, get them clarified from AWS experts on our AWS Community!

53. Which of the following is not an option in security groups?
List of users
Posts
IP addresses
List of protocols
List of users

Top AWS Interview Questions

Top AWS Interview Questions


AWS (Amazon Web Services) is a comprehensive, evolving cloud computing platform provided by Amazon that includes a mixture of infrastructure as a service (IaaS), platform as a service (PaaS) and packaged software as a service (SaaS) offerings. AWS services can offer an organization tools such as compute power, database storage and content delivery services.



AWS INTERVIEW QUESTIONS
1. I have some private servers on premises, also I have distributed some of workload on the public cloud, What is this architecture called?

A) The architecture name is Hybrid Cloud.

2. What does the command do with respect to the Amazon EC2 security groups?
A) Creates a security group for use your account.

3. You have a distributed application that periodically processes large volumes of data across multiple Amazon EC2 Which of the following will meet your requirements?. The application are designed to recover gracefully from Amazon EC2 instance can be failures. You are required to accomplish the task in most cost effective way.Which of the following will meet your requirements?
A) Mostly used on Spot Instances.

4. If I want the instance to run on single tenant hardware, which value do have to set the instance’s tenancy attribute to?
A) Attribute is Dedicated.

5. When will you incur the costs with an Elastic IP address (EIP)?
A) When it is allocated and associated with an stopped instance.

6. Are the Reserved Instances can available for Multi-AZ Deployments?
A) Available for the all instance types.

7. You need to configure an Amazon S3 bucket to the serve static assets for your public-facing of web application. Which method will ensure that all objects an uploaded to the bucket are set to the public read?
A) Configure to the bucket policy to set all objects to public read.

8. A customer wants to the leverage Amazon Simple Storage Service (S3) and Amazon Glacier as a part of their backup and archive infrastructure. The customer plans to the use third-party software to support this integration. Which approach will limit the access of the third party software only to the Amazon S3 an bucket named “company-backup”?
A) A custom IAM user policy is limited to the Amazon S3 API is in “company-backup”.

9. A customer is implemented AWS Storage Gateway with a gateway-cached volume at the main office. An event takes an link between the main and the branch office offline. Which methods will take enable the branch office to the access their data?
A) Launch an new AWS Storage Gateway is instance AMI in Amazon EC2, and the restore from a gateway snapshot.

10. When you need to moving the data over a long distances using the internet, for the instance across countries or continents to the Amazon S3 bucket, which is method or service will you use?
A) Used to Amazon Transfer Acceleration.

11. If you want to the launch Amazon Elastic Compute Cloud (EC2) instances and assign to each instance an predetermined private IP address you should?
A) Launch the instances an Amazon Virtual Private Cloud (VPC).

12. Why do make the subnets?
A) To efficiently utilize to networks that have a large no of hosts.

13. When do subnet is true working?
A) You can attach the multiple subnets to route table.

14. In Cloud Front to take what happens when the content is NOT present an Edge location and the request is an made to it?
A) Cloud Front is delivers to the content is directly from the origin server and the stores it in the cache of the edge location.

15. If launch an standby RDS instance, they will it be in the same Availability Zone as my primary?
A) No result for RDS instance zone.

16. When do I prefer to Provisioned IOPS over the Standard RDS storage?
A) If you have do batch-oriented is workloads.

17. If I am running on my DB Instance a Multi-AZ deployments, can I use to the stand by the DB Instance for read or write a operation along with to primary DB instance?
A) Primary db instance does not working.

18. Which the AWS services will you use to the collect and the process e-commerce data for the near by real-time analysis?
A) Good of Amazon DynamoDB.

19. A company is deploying the new two-tier an web application in AWS. The company has to limited on staff and the requires high availability, and the application requires to complex queries and table joins. Which configuration provides to the solution for company’s requirements?
A) An web application provide on Amazon DynamoDB solution.

20. Which the statement use to cases are suitable for Amazon DynamoDB?
A) The storing metadata for the Amazon S3 objects& The Running of relational joins and complex an updates.

21. Your application has to the retrieve on data from your user’s mobile take every 5 minutes and then data is stored in the DynamoDB, later every day at the particular time the data is an extracted into S3 on a per user basis and then your application is later on used to visualize the data to user. You are the asked to the optimize the architecture of the backend system can to lower cost, what would you recommend do?
A) Introduce Amazon Elasticache to the cache reads from the Amazon DynamoDB table and to reduce the provisioned read throughput.

22. You are running to website on EC2 instances can deployed across multiple Availability Zones with an Multi-AZ RDS MySQL Extra Large DB Instance etc. Then site performs a high number of the small reads and the write per second and the relies on the eventual consistency model. After the comprehensive tests you discover to that there is read contention on RDS MySQL. Which is the best approaches to the meet these requirements?
A) The Deploy Elasti Cache in-memory cache is running in each availability zone and Then Increase the RDS MySQL Instance size and the Implement provisioned IOPS.

23. An startup is running to a pilot deployment of around 100 sensors to the measure street noise and The air quality is urban areas for the 3 months. It was noted that every month to around the 4GB of sensor data are generated. The company uses to a load balanced take auto scaled layer of the EC2 instances and a RDS database with a 500 GB standard storage. The pilot was success and now they want to the deploy take atleast 100K sensors.let which to need the supported by backend. You need to the stored data for at least 2 years to an analyze it. Which setup of following would you be prefer?
A) The Replace the RDS instance with an 6 node Redshift cluster with take 96TB of storage.

24. Let to Suppose you have an application where do you have to render images and also do some of general computing. which service will be best fit your need?
A) Used on Application Load Balancer.

25. How will change the instance give type for the instances, which are the running in your applications tier and Then using Auto Scaling. Where will you change it from areas?
A) Changed to Auto Scaling launch configuration areas.

26. You have an content management system running on the Amazon EC2 instance that is the approaching 100% CPU of utilization. Which option will be reduce load on the Amazon EC2 instance?
A) Let Create a load balancer, and Give register the Amazon EC2 instance with it.

27. What does the Connection of draining do?
A) The re-routes traffic from the instances which are to be updated (or) failed an health to check.

28. When the instance is an unhealthy, it is do terminated and replaced with an new ones, which of the services does that?
A) The survice make a fault tolerance.

29. What are the life cycle to hooks used for the AutoScaling?
A) They are used to the put an additional taken wait time to the scale in or scale out events.

30. An user has to setup an Auto Scaling group. Due to some issue the group has to failed for launch a single instance for the more than 24 hours. What will be happen to the Auto Scaling in the condition?
A) The auto Scaling will be suspend to the scaling process.