Amazon Web Services Interview Questions for Freshers

Top Amazon Web Services Interview Questions

Explain What Is Aws?

AWS stands for Amazon Web Service; it is a collection of remote computing services also known as cloud computing platform. This new realm of cloud computing is also known as IaaS or Infrastructure as a Service.

Mention What Are The Key Components Of Aws?

The key components of AWS are:

Route 53:

A DNS web service

Simple E-mail Service:

It allows sending e-mail using RESTFUL API call or via regular SMTP

Identity and Access Management:

It provides enhanced security and identity management for your AWS account

Simple Storage Device or (S3):

It is a storage device and the most widely used AWS service

Elastic Compute Cloud (EC2):

It provides on-demand computing resources for hosting applications. It is very useful in case of unpredictable workloads

Elastic Block Store (EBS):

It provides persistent storage volumes that attach to EC2 to allow you to persist data past the lifespan of a single EC2

CloudWatch:

To monitor AWS resources, It allows administrators to view and collect key Also, one can set a notification alarm in case of trouble.

Explain What Is S3?

S3 stands for Simple Storage Service. You can use S3 interface to store and retrieve any amount of data, at any time and from anywhere on the web. For S3, the payment model is “pay as you go”.

Explain What Is Ami?

AMI stands for Amazon Machine Image. It’s a template that provides the information (an operating system, an application server and applications) required to launch an instance, which is a copy of the AMI running as a virtual server in the cloud. You can launch instances from as many different AMIs as you need.

Mention What Is The Relation Between An Instance And Ami?

From a single AMI, you can launch multiple types of instances. An instance type defines the hardware of the host computer used for your instance.Each instance type provides different compute and memory capabilities. Once you launch an instance, it looks like a traditional host, and we can interact with it as we would with any computer.

What Does An Ami Include?

An AMI includes the following things:

A template for the root volume for the instance
Launch permissions decide which AWS accounts can avail the AMI to launch instances
A block device mapping that determines the volumes to attach to the instance when it is launched.

How Can You Send Request To Amazon S3?

Amazon S3 is a REST service, you can send request by using the REST API or the AWS SDK wrapper libraries that wrap the underlying Amazon S3 REST API.

Mention What Is The Difference Between Amazon S3 And Ec2?

The difference between EC2 and Amazon S3 is that:

EC2:

It is a cloud web service used for hosting your application
It is like a huge computer machine which can run either Linux or Windows and can handle application like PHP, Python, Apache or any databases.

S3:

It is a data storage system where any amount of data can be stored
It has a REST interface and uses secure HMAC-SHA1 authentication keys.

How Many Buckets Can You Create In Aws By Default?

By default, you can create upto 100 buckets in each of your AWS accounts.

Explain Can You Vertically Scale An Amazon Instance? How?

Yes, you can vertically scale on Amazon instance. For that:

Spin up a new larger instance than the one you are currently running
Pause that instance and detach the root webs volume from the server and discard
Then stop your live instance and detach its root volume
Note the unique device ID and attach that root volume to your new server
And start it again

Explain What Is T2 Instances?

T2 instances are designed to provide moderate baseline performance and the capability to burst to higher performance as required by workload.

In Vpc With Private And Public Subnets, Database Servers Should Ideally Be Launched Into Which Subnet?

With private and public subnets in VPC, database servers should ideally launch into private subnets.

Mention What Are The Security Best Practices For Amazon Ec2?

For secure Amazon EC2 best practices, follow the following steps:

Use AWS identity and access management to control access to your AWS resources
Restrict access by allowing only trusted hosts or networks to access ports on your instance
Review the rules in your security groups regularly
Only open up permissions that your require
Disable password-based login, for instance, launched from your AMI.

Explain How The Buffer Is Used In Amazon Web Services?

The buffer is used to make the system more robust to manage traffic or load by synchronizing different component. Usually, components receive and process the requests in an unbalanced way, With the help of buffer, the components will be balanced and will work at the same speed to provide faster services.

While Connecting To Your Instance What Are The Possible Connection Issues One Might Face?

The possible connection errors one might encounter while connecting instances are:

Connection timed out
User key not recognized by the server
Host key not found, permission denied
Unprotected private key file
Server refused our key or No supported authentication method available
Error using MindTerm on Safari Browser
Error using Mac OS X RDP Client

What Is Amazon Ec2 Service?

Amazon Elastic Compute Cloud (Amazon EC2) is a web service that provides resizable (scalable) computing capacity in the cloud. You can use Amazon EC2 to launch as many virtual servers you need. In Amazon EC2 you can configure security and networking as well as manage storage.Amazon EC2 service also helps in obtaining and configuring capacity using minimal friction.

What Are The Features Of The Amazon Ec2 Service?

As the Amazon EC2 service is a cloud service so it has all the cloud features. Amazon EC2 provides the following features:

Virtual computing environment (known as instances)
Pre-configured templates for your instances (known as Amazon Machine Images – AMIs)
Amazon Machine Images (AMIs) is a complete package that you need for your server (including the operating system and additional software)
Amazon EC2 provides various configurations of CPU, memory, storage and networking capacity for your instances (known as instance type)
Secure login information for your instances using key pairs (AWS stores the public key and you can store the private key in a secure place)
Storage volumes of temporary data is deleted when you stop or terminate your instance (known as instance store volumes)
Amazon EC2 provides persistent storage volumes (using Amazon Elastic Block Store – EBS)

A firewall that enables you to specify the protocols, ports, and source IP ranges that can reach your instances using security groups
Static IP addresses for dynamic cloud computing (known as Elastic IP address)
Amazon EC2 provides metadata (known as tags)

Amazon EC2 provides virtual networks that are logically isolated from the rest of the AWS cloud, and that you can optionally connect to your own network (known as virtual private clouds – VPCs)

What Is Amazon Machine Image And What Is The Relation Between Instance And Ami?

Amazon Web Services provides several ways to access Amazon EC2, like web-based interface, AWS Command Line Interface (CLI) and Amazon Tools for Windows Powershell. First, you need to sign up for an AWS account and you can access Amazon EC2.

Amazon EC2 provides a Query API. These requests are HTTP or HTTPS requests that use the HTTP verbs GET or POST and a Query parameter named Action.

What Is Amazon Machine Image (ami)?

An Amazon Machine Image (AMI) is a template that contains a software configuration (for example, an operating system, an application server, and applications). From an AMI, we launch an instance, which is a copy of the AMI running as a virtual server in the cloud. We can even launch multiple instances of an AMI.

What Is The Relation Between Instance And Ami?

We can launch different types of instances from a single AMI. An instance type essentially determines the hardware of the host computer used for your instance. Each instance type offers different compute and memory capabilities.

After we launch an instance, it looks like a traditional host, and we can interact with it as we would do with any computer. We have complete control of our instances; we can use sudo to run commands that require root privileges.

Explain Storage For Amazon Ec2 Instance.?

Amazon EC2 provides many data storage options for your instances. Each option has a unique combination of performance and durability. These storages can be used independently or in combination to suit your requirements.

There are mainly four types of storages provided by AWS:

Amazon EBS:

Its durable, block-level storage volumes can attached in running Amazon EC2 instance. The Amazon EBS volume persists independently from the running life of an Amazon EC2 instance. After an EBS volume is attached to an instance, you can use it like any other physical hard drive. Amazon EBS encryption feature supports encryption feature.

Amazon EC2 Instance Store:

Storage disk that is attached to the host computer is referred to as instance store. The instance storage provides temporary block-level storage for Amazon EC2 instances. The data on an instance store volume persists only during the life of the associated Amazon EC2 instance; if you stop or terminate an instance, any data on instance store volumes is lost.

Amazon S3:

Amazon S3 provides access to reliable and inexpensive data storage infrastructure. It is designed to make web-scale computing easier by enabling you to store and retrieve any amount of data, at any time, from within Amazon EC2 or anywhere on the web.

Adding Storage:

Every time you launch an instance from an AMI, a root storage device is created for that instance. The root storage device contains all the information necessary to boot the instance. You can specify storage volumes in addition to the root device volume when you create an AMI or launch an instance using block device mapping.

What Is S3? What Is It Used For? Should Encryption Be Used?

S3 stands for Simple Storage Service. You can think of it like FTP storage, where you can move files to and from there, but not mount it like a filesystem. AWS automatically puts your snapshots there, as well as AMIs there. Encryption should be considered for sensitive data, as S3 is a proprietary technology developed by Amazon themselves, and as yet unproven vis-a-vis a security standpoint.

What Is An Ami? How Do I Build One?

AMI stands for Amazon Machine Image. It is effectively a snapshot of the root filesystem. Commodity hardware, servers have a bios that points the master boot record of the first block on a disk. A disk image, though can sit anywhere physically on a disk, so Linux can boot from an arbitrary location on the EBS storage network.

Build a new AMI by first spinning up and instance from a trusted AMI.Then adding packages and components as required. Be wary of putting sensitive data onto an AMI. For instance, your access credentials should be added to an instance after spinup with a database, mount an outside volume that holds your MySQL data after spinup as well.

What Is Auto-scaling? How Does It Work?

Autoscaling is a feature of AWS which allows you to configure and automatically provision and spin up new instances without the need for your intervention.

You do this by setting thresholds and metrics to monitor. When those thresholds are crossed, a new instance of your choosing will be spun up, configured, and rolled into the load balancer pool. Voila, you’ve scaled horizontally without any operator intervention!