What is EBS volume in AWS?
Ravi VishwakarmaAmazon EBS (Elastic Block Store) - Complete Guide
1. What is EBS?
Amazon Elastic Block Store (EBS) is a persistent block-level storage service designed for use with Amazon EC2 instances. It provides highly available, scalable, and low-latency storage volumes that persist independently from the life of an EC2 instance.
2. Key Characteristics
✔ Persistent Storage - Data persists after instance termination
✔ High Availability - Automatically replicated within its Availability Zone (AZ)
✔ Scalable - Resize volumes without downtime (with limitations)
✔ Snapshot Capability - Back up data to S3
✔ Multiple Volume Types - Optimized for different workloads
3. EBS Volume Types
| Volume Type | Description | Use Cases | Max IOPS | Max Throughput |
| gp3 (General Purpose SSD) | Balanced price/performance | Boot volumes, dev/test, most workloads | 16,000 | 1,000 MB/s |
| io1/io2 (Provisioned IOPS SSD) | High performance, low latency | Critical databases, IO-intensive apps | 64,000 (io2) | 4,000 MB/s |
| st1 (Throughput Optimized HDD) | Low-cost HDD, high throughput | Big data, data warehouses, logs | 500 | 500 MB/s |
| sc1 (Cold HDD) | Lowest cost HDD | Infrequently accessed data | 250 | 250 MB/s |
4. EBS vs Instance Store
| Feature | EBS | Instance Store |
| Persistence | Survives instance stop/termination* | Ephemeral (lost on instance stop) |
| Performance | Consistent | Very high (direct-attached) |
| Cost | Additional charge | Included with instance |
| Availability | Across AZ via snapshots | Tied to instance lifecycle |
*Note: By default, EBS root volumes are deleted on termination unless configured otherwise
5. Key EBS Features
Snapshots: Point-in-time backups stored in S3
Multi-Attach: Some volume types can attach to multiple instances (io1/io2)
Encryption: All EBS volumes can be encrypted (AES-256)
Volume Migration: Can detach and reattach to different instances in same AZ
6. Common Use Cases
Database Storage (MySQL, PostgreSQL, Oracle)
Enterprise Applications (SAP, Microsoft SharePoint)
Boot Volumes for EC2 instances
Big Data Analytics (Hadoop, EMR)
Container Storage for Kubernetes/EKS
7. Best Practices
✔ Right-size volumes (monitor with CloudWatch)
✔ Use gp3 for most workloads (better price/performance than gp2)
✔ Enable encryption for sensitive data
✔ Regular snapshots for backup/disaster recovery
✔ Place volumes and instances in same AZ (cross-AZ attachments aren't possible)
8. Pricing Considerations
Pay per GB-month of provisioned storage
Additional costs for:
IOPS (for io1/io2)
Throughput (for st1/sc1)
Snapshots storage
Data transfer between AZs
EBS provides the persistent storage foundation for most AWS workloads, offering flexibility between cost and performance for different application needs. Would you like details on any specific EBS feature? 🚀
Subscribe to my newsletter
Read articles from Ravi Vishwakarma directly inside your inbox. Subscribe to the newsletter, and don't miss out.
Written by