Amazon Web Services Interview Questions and Answers Set 4

31. 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.

32. What Are The Security Best Practices For Amazon Ec2?

  • There are several best practices for secure Amazon EC2. Following are few of them.
  • Use AWS Identity and Access Management (AM) to control access to your AWS resources.
  • Restrict access by only allowing trusted hosts or networks to access ports on your instance.
  • Review the rules in your security groups regularly, and ensure that you apply the principle of least
  • Privilege — only open up permissions that you require.
  • Disable password-based logins for instances launched from your AMI. Passwords can be found or cracked, and are a security risk.

33. Explain Stopping, Starting, And Terminating An Amazon Ec2 Instance?

Stopping and Starting an instance: When an instance is stopped, the instance performs a normal shutdown and then transitions to a stopped state. All of its Amazon EBS volumes remain attached, and you can start the instance again at a later time. You are not charged for additional instance hours while the instance is in a stopped state.

Terminating an instance: When an instance is terminated, the instance performs a normal shutdown, then the attached Amazon EBS volumes are deleted unless the volume’s deleteOnTermination attribute is set to false. The instance itself is also deleted, and you can’t start the instance again at a later time.

34.What is S3? What is it used for? Should encryption be used?

S3 implies for Simple Storage Service. You can believe it similar ftp warehouse, wherever you can transfer records to and from beyond, merely not uprise it similar to a filesystem. AWS automatically places your snaps there, at the same time AMIs there. sensitive data is treated with Encryption, as S3 is an exclusive technology promoted by Amazon themselves, and as still unproven vis-a-vis a protection viewpoint.

35. What is an AMI? How do I build one?

AMI holds for Amazon Machine Image. It is efficiently a snap of the source filesystem. Products appliance servers have a bio that shows the master drive report of the initial slice on a disk. A disk form though can lie anyplace physically on a disc, so Linux can boot from an absolute position on the EBS warehouse interface.

Create a unique AMI at beginning rotating up and instance from a granted AMI. Later uniting combinations and components as needed. Comprise wary of setting delicate data over an AMI (learn salesforce online). For instance, your way credentials should be joined to an instance later spinup. Among a database, mount an external volume that carries your MySQL data next spinup actually enough.

36. Can I Vertically Scale An Amazon Instance? How?

Yes.This is an incredible feature of AWS and cloud virtualization. Spin up a new larger instance than the one you are currently running. Pause that instance and detach the root ebs volume from this server and discard. Then stop your live instance, detach its root volume. Note down the unique device ID and attach that root volume to your new server. And then start it again. Voila, you have scaled vertically in-place!!

37. Define Auto Scaling?

Answer: Auto-scaling is one of the conspicuous characteristics feature of AWS anywhere it authorizes you to systematize and robotically obligation and twist up new models externally that necessary for your entanglement. This can be accomplished by initiating brims and metrics to view.If these proposals are demolished, the latest model of your preference will be configured, wrapped up and cloned into the weight administrator panel.

38. Which automation gears can help with spinup services?

For the written scripts we can use spinup services with the help of API tools.These scripts could be coded in bash, Perl, or any another language of your choice.There is one more alternative that is patterned control and stipulating devices before-mentioned as a dummy or advanced descendant. A machine termed as Scalar can likewise be utilized and ultimately we can proceed with a constrained expression like a RightScale.

39. Is it possible to scale an Amazon instance vertically? How?

Yes, it is possible to scale an Amazon instance vertically because of an unbelievable characteristic of cloud virtualization and AWS. Spinup is a huge case while correlated to the one which you are working with. Let up the case and distribute the source EBS bulk of this server and eliminate. Subsequent, end your existing instance, exclude its root volume. Enter down the peculiar device ID and join source volume to your fresh server and begin it repeatedly. This is the way to scaling vertically in position.

40. How the processes start, stop and terminate works?

Starting and stopping of an instance: If an instance goes arrested or died, the instance performs a normal power cut and then transfer over to a sealed area. You can build the case then for all the EBS masses of Amazon persist and associated. If an instance is in ending state, suddenly you will not get charged to the additional instance

Finishing the instance: If an instance goes stopped it serves to perform a standard blackout, therefore the EBS capacities which are connected will get excluded save the volume’s delete On Termination feature is fixed to zero. In such instances, the instance will get eliminated and cannot set it up afterward.