Amazon EBS: Storage Solutions

• Amazon Elastic Block Store (Amazon EBS) is a high-performance block storage service for use with Amazon EC2 instances.
• It enables the creation and management of persistent storage volumes for running databases, applications, and storing critical data.
• EBS is designed as a low-latency, high-throughput, scalable storage solution for workloads requiring frequent read and write operations.
• EBS provides persistent storage that survives EC2 instance failures, unlike instance store volumes.

Key Concepts of Amazon EBS

• An EBS volume is a virtual disk that can be attached to an EC2 instance, ranging from 1 GB to 16 TB.
• EBS volumes offer persistent storage that remains intact even after the EC2 instance is stopped or terminated.
• Volumes are replicated within the availability zone (AZ) to prevent data loss and ensure high durability.
• EBS provides block-level storage, storing data in blocks, allowing applications and operating systems to interact with the data as if it were directly attached.
• EBS volumes are persistent, ensuring data remains intact even if the attached EC2 instance is stopped, restarted, or terminated.
• There are several types of EBS volumes, designed for different use cases, depending on performance needs, IOPS, throughput, and cost.

Types of EBS Volumes

• General Purpose SSD (gp3 and gp2) are suitable for most workloads like small-to-medium-sized databases, development environments, and boot volumes.
• gp3 offers a baseline performance of 3,000 IOPS and lets users scale IOPS and throughput independently of storage capacity.
• gp2 provides a balance of price and performance with a burst capability of up to 16,000 IOPS, depending on volume size.
• Provisioned IOPS SSD (io2 and io1) are designed for I/O-intensive workloads requiring low-latency and high-throughput.
• io2 offers up to 64,000 IOPS and greater durability (99.999%).
• io1 offers up to 64,000 IOPS, but with lower durability compared to io2.
• Throughput Optimized HDD (st1) is ideal for big data and data warehouse workloads requiring high throughput.
• st1 is suitable for applications where throughput is more important than IOPS.
• Cold HDD (sc1) is designed for less frequently accessed data, like archival storage or backup data that does not require high throughput or IOPS.
• sc1 is cost-effective for large volumes of infrequently accessed data.
• Magnetic (standard) is an older, legacy volume type replaced by SSD options, offering lower performance and should be used only for specific legacy applications.
• Snapshots are backups of EBS volumes, stored in Amazon S3, capturing the state of the volume at a specific point in time.
• Snapshots are incremental, saving only the changes since the last snapshot, reducing storage costs and backup time.
• EBS snapshots are key for disaster recovery and data backup, used to create new volumes or restore data in the event of failure.
• EBS volume snapshots can be used in another region
• AWS ensures data consistency by temporarily pausing operations before creating a snapshot.
• Lifecycle policies can be defined for EBS snapshots
• Snapshots are S3 Compatible
• Delete on termination determines whether the volume should be automatically deleted when it's associated EC2 is terminated.
• EBS volumes can be attached to or detached from an EC2 instance.
• EBS volumes can be attached to an EC2 instance (one volume per instance) or to multiple instances (for multi-attach scenarios). When attached, they are recognized by the operating system as block devices.
• Volumes can be detached from an EC2 instance safely and then attached to another instance for data migration or failover purposes.
• EBS volumes are elastic, as they can be resized dynamically without downtime.
• Users can increase the size of an EBS volume or change the type of volume to accommodate changing performance or capacity needs.

How EBS Works

• When creating an EBS volume, one must specify the size, volume type, and the availability zone (AZ) in which the volume will reside.
• Once created, the EBS volume is ready to be attached to an EC2 instance.
• EBS volumes can be attached to EC2 instances either during instance creation or after the instance has been launched.
• The volume appears to the EC2 instance as a raw block device, and the operating system then formats the volume, assigns it a filesystem, and mounts it for use.
• After being attached, the EC2 instance can read and write data to the EBS volume as if it were a local hard disk.
• Data stored on EBS volumes is persistent, and the volume is not lost even if the EC2 instance is stopped or terminated, unless explicitly deleted.
• EBS volumes can be resized without downtime.
• After resizing a volume, one may need to extend the file system from within the operating system.
• Snapshots of EBS volumes can be created to back up data.
• Snapshots are stored in Amazon S3 and can be restored to create new EBS volumes at any time.
• Snapshots can also be used to clone an EBS volume or copy volumes between regions for disaster recovery.
• EBS volumes are automatically replicated within their availability zone to ensure durability and availability.
• If even more durability is required, back up volumes using snapshots or use Amazon EBS Multi-Attach to allow multiple EC2 instances to access the same volume for high-availability scenarios.

Benefits of Amazon EBS

• EBS volumes are designed to be highly durable with 99.999% availability.
• EBS volumes are automatically replicated within the availability zone to protect against hardware failures.
• The size, performance, and type of volumes can be scaled independently of EC2 instances.
• Scaling flexibility allows users to start small and scale up as their storage needs grow.
• EBS offers different volume types optimized for different workloads.
• EBS can provide the appropriate performance level for any application, whether high throughput, low latency, or high IOPS are needed.
• Snapshots provide a reliable and cost-effective method to back up data, ensuring data persistence and disaster recovery capability.
• Users pay only for the storage they use.
• One can choose the volume type that fits their workload to optimize for cost and performance.
• EBS volumes are encrypted by default (using AWS Key Management Service (KMS)) to ensure data confidentiality and compliance.
• Access to volumes can be controlled using IAM policies.

Use Cases for EBS

• EBS volumes are commonly used to store databases like MySQL, PostgreSQL, Oracle, and SQL Server.
• EBS supports high-performance, persistent storage needed for database systems.
• High-throughput EBS volumes (such as st1 or io2) are ideal for big data analytics and data warehousing use cases.
• Applications like ERP (Enterprise Resource Planning) systems that require reliable, high-performance storage can rely on EBS for persistent storage.
• EBS snapshots are commonly used for backup purposes and disaster recovery scenarios, as they allow users to restore data to any point in time.
• EBS is commonly used to provide file storage systems, such as a Network File System (NFS) or Windows File Server, for EC2 instances.

Explore Amazon EBS for low-latency, high-throughput storage with data persistence. Learn about EBS features like ensuring data persistence on EC2, provisioning virtual disks, volume size, and block storage.