Amazon Elastic Block Store (EBS) is a high-performance block storage service designed for use with Amazon EC2 instances. Think of EBS as virtual hard drives that you can attach to your cloud servers, providing persistent storage that remains intact even when EC2 instances are stopped or terminated.…Amazon Elastic Block Store (EBS) is a high-performance block storage service designed for use with Amazon EC2 instances. Think of EBS as virtual hard drives that you can attach to your cloud servers, providing persistent storage that remains intact even when EC2 instances are stopped or terminated.
Key Features of Amazon EBS:
1. **Persistence**: Unlike instance store volumes, EBS volumes retain data independently of the EC2 instance lifecycle. Your data stays safe when you stop or restart your instance.
2. **Volume Types**: EBS offers multiple volume types optimized for different workloads:
- General Purpose SSD (gp2/gp3): Balanced price and performance for most workloads
- Provisioned IOPS SSD (io1/io2): High-performance for critical applications
- Throughput Optimized HDD (st1): Low-cost storage for frequently accessed data
- Cold HDD (sc1): Lowest cost for infrequently accessed data
3. **Snapshots**: EBS allows you to create point-in-time snapshots of your volumes, which are stored in Amazon S3. These snapshots enable backup, disaster recovery, and volume migration across Availability Zones.
4. **Encryption**: EBS provides built-in encryption capabilities to protect data at rest and data in transit between volumes and instances.
5. **Scalability**: You can easily resize volumes and change volume types based on your evolving needs, ensuring flexibility as your requirements grow.
6. **Availability Zone Specific**: Each EBS volume exists within a single Availability Zone, and can only be attached to EC2 instances in that same zone.
Common Use Cases:
- Database storage
- Enterprise applications
- Development and testing environments
- Boot volumes for EC2 instances
For the Cloud Practitioner exam, remember that EBS provides durable, block-level storage that is essential for applications requiring consistent and low-latency performance.
Amazon EBS: Complete Guide for AWS Cloud Practitioner Exam
What is Amazon EBS?
Amazon Elastic Block Store (EBS) is a high-performance block storage service designed for use with Amazon EC2 instances. Think of EBS volumes as virtual hard drives that you can attach to your EC2 instances to store data persistently.
Why is Amazon EBS Important?
EBS is crucial because it provides persistent storage that exists independently of EC2 instances. Unlike instance store volumes (ephemeral storage), EBS volumes retain your data even when the associated EC2 instance is stopped or terminated. This makes EBS essential for:
• Database storage • Boot volumes for EC2 instances • Applications requiring frequent read/write operations • Data that must survive instance failures
How Does Amazon EBS Work?
EBS volumes are network-attached storage that connect to EC2 instances within the same Availability Zone. Key characteristics include:
• Availability Zone Specific: EBS volumes are created in a specific AZ and can only attach to instances in that same AZ • Snapshots: You can create point-in-time backups called snapshots, which are stored in Amazon S3 and can be used to create new volumes in any AZ • Volume Types: Different types optimized for various workloads (SSD-based for transactional workloads, HDD-based for throughput-intensive workloads) • Encryption: EBS supports encryption at rest using AWS KMS keys
EBS Volume Types:
• General Purpose SSD (gp2/gp3): Balanced price and performance for most workloads • Provisioned IOPS SSD (io1/io2): High-performance for mission-critical applications • Throughput Optimized HDD (st1): Low-cost HDD for frequently accessed, throughput-intensive workloads • Cold HDD (sc1): Lowest cost HDD for less frequently accessed workloads
Exam Tips: Answering Questions on Amazon EBS
Tip 1: Remember that EBS provides block-level storage, not object storage (that is S3) or file storage (that is EFS).
Tip 2: EBS volumes are AZ-locked. To move data to another AZ, you must create a snapshot first, then create a new volume from that snapshot in the target AZ.
Tip 3: When a question mentions databases, boot volumes, or applications needing low-latency access to data on EC2, EBS is typically the correct answer.
Tip 4: EBS snapshots are incremental - only changed blocks are saved after the initial snapshot, reducing storage costs.
Tip 5: For questions about high IOPS requirements or database workloads, look for Provisioned IOPS (io1/io2) as the answer.
Tip 6: EBS volumes can be resized and have their type changed while in use, demonstrating the elasticity of AWS services.
Tip 7: If the question asks about cost-effective storage for infrequently accessed data on EC2, Cold HDD (sc1) is the most economical choice.
Common Exam Scenarios:
• Need persistent storage for EC2? → EBS • Need to backup EBS data? → EBS Snapshots • Need storage across multiple AZs? → Use snapshots to replicate • Need encryption for data at rest on EC2? → EBS Encryption