Question-3: You are working in AcmeShell Inc. their accounting department submit tax on monthly basis for their employee as well for the services provided by the company to their client and they need to store all these records which are documented and should be protected by deletion and any kind of data loss. Which of the following is best suitable solutions from AWS?

1. You will create an EBS volume and attach it to one of the EC2 instance and install accounting application on it, which will encrypt the document and store on it. You will also replicate same EBS volume in another region using sync process.
2. You should create one copy in EBS volume and another copy in the instance store of EC2 instance.
3. You should use AWS Glacier storage service
4. You can use S3 storage service with versioning enabled
5. You should use DynamoDB where you can stored documents as well

Correct Answer: 4

Exp: What is the requirement in question: storing document which should be protected from accidental deletion? All options are storage S3:  Simple Storage service, it is used to store objects like Documents, Images and video files. It could be a correct option. Is it durable? Answer is yes. Once you store your object in it. It will remain in it, until you delete it explicitly and you can do the faster retrieval as well. Can document accidently deleted from S3 bucket, if user has permission to do so, yes it can be deleted. But if you enable versioning than all the versions of the document will be saved, by default. Hence, this is the most suitable answer for given requirement. Please note that, whatever extra space is taken by the multiple version of documents will attract charges. Versioning is free but storage taken by versioned document will be charged.

DynamoDB: Not at all good for Document storage, hence eliminate this. It is a No-SQL storage to store key-vale data for faster retrieval. 

Glacier: This is also an object storage, but it is used for archival, any data which is very frequently accessed should use this storage. However, you may get confused with this option. But to avoid accidental deletion, enabling versioning on the S3 bucket will give you correct choice.

EBS: Elastic block storage, it is a storage. But you generally not use this storage for given requirement. EBS can be used for creating databases on it. Like you want to install your own MySQL service. You will be using EBS. And to access data stored in EBS volume, EBS always has to be attached with an EC2 instance.

Instance store: Anything you will store in instance store, will be deleted as soon as you terminate your instance. Hence, this can never be a correct choice for given requirement.