Storage and Databases Flashcards
What is Amazon Elastic Block Store (Amazon EBS)?
Amazon Elastic Block Store (Amazon EBS) is a service that provides block-level storage volumes that you can use with Amazon EC2 instances. If you stop or terminate an Amazon EC2 instance, all the data on the attached EBS volume remains available.
What is an EBS Snapshot?
An EBS snapshot is an incremental backup. This means that the first backup taken of a volume copies all the data. For subsequent backups, only the blocks of data that have changed since the most recent snapshot are saved.
What is an instance store?
An instance store provides temporary block-level storage for an Amazon EC2 instance. An instance store is disk storage that is physically attached to the host computer for an EC2 instance, and therefore has the same lifespan as the instance. When the instance is terminated, you lose any data in the instance store.
What is S3 Standard?
S3 Standard
Designed for frequently accessed data
Stores data in a minimum of three Availability Zones
S3 Standard-IA (Infrequent Access)
Similar to S3 Standard but has a lower storage price and higher retrieval price
S3 Standard-IA is ideal for data infrequently accessed but requires high availability when needed. Both S3 Standard and S3 Standard-IA store data in a minimum of three Availability Zones. S3 Standard-IA provides the same level of availability as S3 Standard but with a lower storage price and a higher retrieval price.
S3 One Zone-Infrequent Access (S3 One Zone-IA)
- Stores data in a single Availability Zone
- Has a lower storage price than S3 Standard-IA
Compared to S3 Standard and S3 Standard-IA, which store data in a minimum of three Availability Zones, S3 One Zone-IA stores data in a single Availability Zone. This makes it a good storage class to consider if the following conditions apply:
- You want to save costs on storage.
- You can easily reproduce your data in the event of an Availability Zone failure.
S3 Intelligent-Tiering
- Ideal for data with unknown or changing access patterns
- Requires a small monthly monitoring and automation fee per object
In the S3 Intelligent-Tiering storage class, Amazon S3 monitors objects’ access patterns. If you haven’t accessed an object for 30 consecutive days, Amazon S3 automatically moves it to the infrequent access tier, S3 Standard-IA. If you access an object in the infrequent access tier, Amazon S3 automatically moves it to the frequent access tier, S3 Standard.
S3 Glacier
- Low-cost storage designed for data archiving
- Able to retrieve objects within a few minutes to hours
S3 Glacier is a low-cost storage class that is ideal for data archiving. For example, you might use this storage class to store archived customer records or older photos and video files.
S3 Glacier Deep Archive
- Lowest-cost object storage class ideal for archiving
- Able to retrieve objects within 12 hours
When deciding between Amazon S3 Glacier and Amazon S3 Glacier Deep Archive, consider how quickly you need to retrieve archived objects. You can retrieve objects stored in the S3 Glacier storage class within a few minutes to a few hours. By comparison, you can retrieve objects stored in the S3 Glacier Deep Archive storage class within 12 hours.
Difference between Elastic Block Store (EBS) and Elastic File System (EFS)
An Amazon EBS volume stores data in a single Availability Zone.
To attach an Amazon EC2 instance to an EBS volume, both the Amazon EC2 instance and the EBS volume must reside within the same Availability Zone.
Amazon EFS is a regional service. It stores data in and across multiple Availability Zones.
The duplicate storage enables you to access data concurrently from all the Availability Zones in the Region where a file system is located.
What is file storage?
In file storage, multiple clients (such as users, applications, servers, and so on) can access data that is stored in shared file folders. In this approach, a storage server uses block storage with a local file system to organize files. Clients access data through file paths.
What use cases is file storage ideal for?
Compared to block storage and object storage, file storage is ideal for use cases in which a large number of services and resources need to access the same data at the same time.
What is Amazon Elastic File Service (EFS)?
Amazon Elastic File System (Amazon EFS) is a scalable file system used with AWS Cloud services and on-premises resources. As you add and remove files, Amazon EFS grows and shrinks automatically. It can scale on demand to petabytes without disrupting applications.
What is a relational database?
In a relational database, data is stored in a way that relates it to other pieces of data.
Relational databases use structured query language (SQL) to store and query data.
What is AWS Database Migration Service (AWS DMS)?
AWS Database Migration Service (AWS DMS) enables you to migrate relational databases, nonrelational databases, and other types of data stores.
