Interview questions on Evaluation of storage solutions
Here are some commonly asked interview questions regarding the evaluation of AWS storage solutions
1. What is the main difference between Amazon S3 and Amazon EBS?
Answer: Amazon S3 (Simple Storage Service) is an object-based storage solution that is designed for scalability, durability, and availability. S3 is suitable for storing unstructured data such as images, videos, backups, and large log files. On the other hand, Amazon EBS (Elastic Block Store) is a block-based storage solution that is designed to be used as the primary storage for Amazon EC2 instances. EBS provides low latency and high throughput block-level storage that is suitable for use as the root device for an EC2 instance.
2. What are the use cases for Amazon EFS?
Answer: Amazon EFS (Elastic File System) is a file-based storage solution that is designed to be used as a file system in the cloud. EFS provides scalable storage that can be used as a shared file system between multiple EC2 instances, making it suitable for applications that require shared access to data, such as big data analytics, media processing, content management, and web serving.
3. How does Amazon S3 compare to Amazon EFS in terms of scalability?
Answer: Both Amazon S3 and Amazon EFS provide highly scalable storage solutions. S3 is designed to scale from zero to petabytes of data, and can automatically handle the storage and retrieval of billions of objects. On the other hand, EFS is designed to provide scalable file storage, and can automatically grow and shrink in response to changes in demand.
4. What are the costs associated with using Amazon S3, Amazon EBS, and Amazon EFS?
Answer: The costs associated with using these storage solutions vary based on the specific use case and the amount of storage and data transfer required. S3 charges for the amount of data stored, the number of requests made, and the amount of data transferred. EBS charges for the amount of storage used, the amount of data transferred, and the number of I/O operations performed. EFS charges for the amount of storage used and the amount of data transferred.
5. When should you use Amazon S3 vs Amazon EBS vs Amazon EFS?
Answer: The choice between S3, EBS, and EFS depends on the specific use case and the requirements of the application. If you need to store unstructured data such as images, videos, backups, and large log files, then S3 is the appropriate choice. If you need to store data that requires low latency and high throughput block-level storage, such as the root device for an EC2 instance, then EBS is the appropriate choice. If you need to store data that requires a shared file system, such as big data analytics, media processing, content management, and web serving, then EFS is the appropriate choice.
6. Can Amazon S3 be used as a database?
Answer: Amazon S3 is not designed to be used as a database. It is an object-based storage solution that is optimized for storing and retrieving large amounts of unstructured data. However, some applications may use S3 as a data store by storing objects in S3 and using the Amazon S3 API to interact with the data.
7. What are the security features of Amazon EBS?
Answer: Amazon EBS provides several security features to protect data stored on its volumes. These include the ability to encrypt data at rest using Amazon EBS encryption, control over who can access the data using AWS Identity and Access Management (IAM) policies, and the ability to store data in Virtual Private Clouds (VPCs) that are isolated from the public internet.
8. How does Amazon EFS compare to NFS in terms of performance?
Answer: Amazon EFS is designed to provide high performance for file-based storage in the cloud. In terms of performance, EFS provides similar latency and throughput characteristics as NFS, but with the added benefits of being highly available, scalable, and fully managed by AWS.
9. How does Amazon S3 compare to Amazon Glacier in terms of data retrieval times?
Answer: Amazon Glacier is a low-cost storage solution that is designed for long-term data archiving and backup. Data retrieval times from Glacier can range from several minutes to several hours, depending on the size of the data being retrieved and the retrieval request type. In comparison, data retrieval times from Amazon S3 are typically in the order of milliseconds to seconds.
10. What is the maximum size of a single Amazon EBS volume?
Answer: The maximum size of a single Amazon EBS volume depends on the instance type that the volume is attached to. For example, gp2 volumes can range in size from 1 GiB to 16 TiB, while io1 volumes can range in size from 100 GiB to 16 TiB.
11. Can Amazon EBS be used as a boot volume?
Answer: Yes, Amazon EBS can be used as a boot volume for an Amazon EC2 instance. An Amazon EBS volume can be attached to an EC2 instance as the root device, allowing the instance to boot and run an operating system from the EBS volume.
12. What is the durability of data stored in Amazon S3?
Answer: Amazon S3 provides high durability for data stored in the service. By default, S3 stores data across multiple devices in multiple facilities, and is designed to provide 99.999999999% durability of objects over a given year.
13. What is the maximum number of Amazon EFS file systems that can be created in a single AWS account?
Answer: There is no hard limit to the number of Amazon EFS file systems that can be created in a single AWS account. The number of file systems that can be created is limited by the available resources in the AWS region where the file systems are created.
14. Can Amazon EBS be used to store data for multiple EC2 instances at the same time?
Answer: No, an Amazon EBS volume can only be attached to a single EC2 instance at a time. To store data that can be accessed by multiple EC2 instances, you would need to use a shared file system such as Amazon EFS.
15. Can Amazon S3 be used to store and serve static website content?
Answer: Yes, Amazon S3 can be used to store and serve static website content. S3 provides a low-cost and scalable solution for storing and serving static website content such as HTML, CSS, JavaScript, and images. By using S3, you can serve your website to visitors with low latency and high data transfer rates. You can also take advantage of features like versioning, access control, and website hosting to manage and deliver your website content.
16. What is the difference between Amazon S3 and Amazon EBS?
Answer: Amazon S3 is an object-based storage service that is optimized for storing and retrieving large amounts of unstructured data. Amazon EBS is a block-based storage service that provides raw block-level access to the storage for use with Amazon EC2 instances. S3 is designed for data archiving and backup, while EBS is designed for use as a primary storage device for Amazon EC2 instances.
17. What is the impact of changing the performance level of an Amazon EBS volume?
Answer: The performance level of an Amazon EBS volume can be changed, and the impact of the change depends on the specific use case. If you increase the performance level of an EBS volume, you can expect higher throughput and I/O performance, but this may come at a higher cost. If you decrease the performance level, you can expect lower costs, but also lower performance.
18. Can Amazon S3 be used to store and serve dynamic web content?
Answer: Amazon S3 is not well suited for serving dynamic web content as it is an object-based storage solution optimized for storing and retrieving large amounts of unstructured data. For dynamic web content, you may want to consider using Amazon EC2 instances and Amazon EBS volumes to host and serve your content.
19. How does Amazon EFS handle data redundancy and durability?
Answer: Amazon EFS provides multiple levels of redundancy and durability to protect your data stored in the service. EFS uses multiple storage nodes and multiple Availability Zones to store data, and it automatically replicates your data across multiple storage nodes to ensure that your data is always available, even in the event of a storage node failure.
20. Can Amazon S3 be used to store sensitive data?
Answer: Yes, Amazon S3 can be used to store sensitive data, but you need to take proper security measures to protect the data. For example, you can encrypt the data at rest using Amazon S3 server-side encryption, or encrypt the data in transit using SSL/TLS. You can also use IAM policies and VPCs to control access to the data.
21. Can an Amazon EBS volume be attached to multiple EC2 instances at the same time?
Answer: No, an Amazon EBS volume cannot be attached to multiple EC2 instances at the same time. An EBS volume can only be attached to one EC2 instance at a time.
22. What is the impact of increasing the size of an Amazon EBS volume?
Answer: The impact of increasing the size of an Amazon EBS volume depends on the specific use case. In general, increasing the size of an EBS volume will provide more storage capacity, but it may also increase the cost of using the volume. Additionally, the process of increasing the size of an EBS volume may cause the EC2 instance that the volume is attached to to become unavailable for a brief period of time.
23. How does Amazon S3 handle data redundancy and durability?
Answer: Amazon S3 provides multiple levels of redundancy and durability to protect your data stored in the service. S3 stores your data across multiple devices in multiple facilities, and it automatically replicates your data across multiple facilities to ensure that your data is always available, even in the event of a device failure or a facility outage.
24. Can Amazon EFS be used as a boot volume for an EC2 instance?
Answer: No, Amazon EFS cannot be used as a boot volume for an EC2 instance. EFS is a file-based storage service and is not designed to be used as a boot volume for EC2 instances. To boot an EC2 instance, you need to use a block-based storage solution, such as Amazon EBS, that provides raw block-level access to the storage.
25. What is the difference between Amazon EBS and Amazon EFS in terms of scalability?
Answer: Amazon EBS is a block-based storage service that provides raw block-level access to the storage for use with Amazon EC2 instances. EBS volumes can be resized and attached to EC2 instances as needed, allowing you to scale your storage capacity up or down as your needs change.
Amazon EFS, on the other hand, is a file-based storage service that provides a scalable, file storage system for use with Amazon EC2 instances. With EFS, you can easily scale your storage capacity up or down by simply changing the size of the file system. Additionally, EFS supports the ability to mount the file system on multiple EC2 instances, allowing you to scale your storage capacity across multiple instances as your needs change.
