AWS Interview Questions – Set 04

What is the use of Amazon Transfer Acceleration Service?

An Amazon Transfer Acceleration Service is a service that enables fast and secure transfer of data between your client and S3 bucket.

What is an EIP?

EIP (Elastic IP address) is a service provided by an EC2 instance. It is basically a static IP address attached to an EC2 instance. This address is associated with your AWS account not with an EC2 instance. You can also disassociate your EIP address from your EC2 instance and map it to another EC2 instance in your AWS account.

How will you access the data on EBS in AWS?

EBS stands for Elastic Block Store. It is a virtual disk in a cloud that creates the storage volume and attach it to the EC2 instances. It can run the databases as well as can store the files. All the files that it store can be mounted as a file system which can be accessed directly.

What are the two types of access that you can provide when you are creating users?

There are two types of access:

  • Console Access
    If the user wants to use the Console Access, a user needs to create a password to login in an AWS account.
  • Programmatic access
    If you use the Programmatic access, an IAM user need to make an API calls. An API call can be made by using the AWS CLI. To use the AWS CLI, you need to create an access key ID and secret access key.

What is AWS Lambda?

AWS Lambda is a compute service that runs your code without managing servers. Lambda function runs your code whenever needed. You need to pay only when your code is running.

Difference between Stopping and Terminating the instances?

Stopping: You can stop an EC2 instance and stopping an instance means shutting down the instance. Its corresponding EBS volume is still attached to an EC2 instance, so you can restart the instance as well.

Terminating: You can also terminate the EC2 instance and terminating an instance means you are removing the instance from your AWS account. When you terminate an instance, then its corresponding EBS is also removed. Due to this reason, you cannot restart the EC2 instance.

What are the types of AMI provided by AWS?

There are two types of AMI provided by AWS:

  • Instance store backed
  • An instance-store backed is an EC2 instance whose root device resides on the virtual machine’s hard drive.
  • When you create an instance, then AMI is copied to the instance.
  • Since “instance store-backed” instances root device is stored in the virtual machine’s hard drive, so you cannot stop the instance. You can only terminate the instance, and if you do so, the instance will be deleted and cannot be recovered.
  • If the virtual machine’s hard drive fails, then you can lose your data.
  • You need to leave this instance-store instance in a running state until you are completely done with it.
  • You will be charged from the moment when your instance is started until your instance is terminated.
  • EBS backed
  • An “EBS backed” instance is an EC2 instance that uses EBS volume as a root device
  • EBS volumes are not tied to a virtual hardware, but they are restricted to an availability zone. This means that EBS volume is moved from one machine to another machine within the same availability zone.
  • If the virtual machine’s fails, then the virtual machine can be moved to another virtual machine.
  • The main advantage of “EBS backed” over “instance store-backed” instances is that it can be stopped. When an instance is in a stopped state, then EBS volume can be stored for a later use. The virtual machine is used for some other instance. In stopped state, you are not charged for the EBS storage.

What is the minimum and maximum size that you can store in S3?

The minimum size of an object that you can store in S3 is 0 bytes and the maximum size of an object that you can store in S3 is 5 TB.

How can you control the security to your VPC?

You can control the security to your VPC in two ways:

Security Groups

  • It acts as a virtual firewall for associated EC2 instances that control both inbound and outbound traffic at the instance level.

Network access control lists (NACL)

  • It acts as a firewall for associated subnets that control both inbound and outbound traffic at the subnet level.

What are the different storage classes in S3?

Storage classes are used to assist the concurrent loss of data in one or two facilities. Each object in S3 is associated with some storage class. Amazon S3 contains some storage classes in which you can store your objects. You can choose a storage class based on your requirements and these storage classes offer high durability.