AWS Cloud Fundamentals #14: EBS and Instance Store Storage Services

In the previous article, we explored AWS S3 object storage—its core concepts and common use cases. This article continues our deep dive into AWS storage services, focusing on EBS (Elastic Block Store) and instance store, two critical storage options for EC2 instances.

EBS (Elastic Block Store)

EBS is a persistent block-storage service offered by AWS, delivering high-performance storage solutions for EC2 instances. EBS-backed volumes enable data sharing across multiple instances and retain data across EC2 instance restarts.

Key Features of EBS

• Persistence: Data on EBS volumes remains intact even after an instance is stopped or rebooted.
• High Availability: EBS automatically replicates data within an Availability Zone to provide point-in-time fault tolerance.
• Flexibility: Supports multiple volume types—including SSD and HDD—to meet diverse workload requirements.

EBS Volume Types

AWS offers several EBS volume types, primarily:

1. General Purpose SSD (gp2/gp3): Ideal for a broad range of workloads, offering a balanced mix of performance and cost-efficiency.
2. Provisioned IOPS SSD (io1/io2): Designed for latency-sensitive, high-throughput database workloads requiring predictable, high IOPS.
3. Magnetic HDD (st1/sc1): Optimized for large-scale, sequential-access workloads such as big data analytics and low-cost archival storage.

Common Use Cases for EBS

• Web Applications: Provides durable, scalable storage for dynamic websites and application backends.
• Databases: Delivers high IOPS and low-latency storage for relational (e.g., MySQL, PostgreSQL) and NoSQL databases.
• Data Warehouses: Stores intermediate results and final outputs from large-scale analytical processing.

Example: Creating and Mounting an EBS Volume

Here’s a step-by-step guide to creating an EBS volume and attaching it to an EC2 instance via the AWS Management Console:

1. Log in to the AWS Management Console and navigate to the EC2 Dashboard.

2. Under Elastic Block Store, select Volumes.

3. Click Create Volume, then specify the desired volume type, size, and Availability Zone.

4. After creation, select the new volume → choose Actions → Attach Volume, and select your target EC2 instance.

5. SSH into the EC2 instance and run the following commands to format and mount the volume (replace X with the actual device letter identifier, e.g., f):

   sudo mkfs -t ext4 /dev/xvdX  # X is the device letter identifier for your EBS volume
   sudo mkdir /mnt/mydata
   sudo mount /dev/xvdX /mnt/mydata
   

Data Backup and Recovery

EBS snapshots provide simple, efficient backup and recovery. Snapshots are incremental, point-in-time backups of EBS volumes—and can be restored to new EBS volumes on demand. To create a snapshot, use:

aws ec2 create-snapshot --volume-id vol-xxxxxxxx --description "My EBS Snapshot"

Instance Store

Instance store is ephemeral, physically attached storage directly integrated with an EC2 instance. Unlike EBS, instance store lifetime is tightly coupled to the instance lifecycle: data is lost when the instance is stopped or terminated.

Key Characteristics of Instance Store

• High Performance: Delivers extremely high throughput and ultra-low latency due to direct physical attachment to the host hardware.
• Ephemeral Nature: Designed exclusively for temporary data—ideal for transient computation outputs—but does not persist beyond the instance’s lifetime.

Typical Use Cases

• Temporary Data Processing: Storing intermediate outputs during compute-intensive tasks—for example, video transcoding or iterative data analysis steps.
• Caching and Scratch Storage: Serving as application-level cache, temporary file space, or swap space.

Important Considerations

Because data on instance store is irrecoverable upon instance termination or reboot, robust external backup strategies are essential if any data must be preserved.

Summary

This tutorial detailed the core characteristics, practical use cases, and operational procedures for both AWS EBS and instance store. EBS delivers persistent, highly available block storage—making it ideal for databases and mission-critical applications. In contrast, instance store excels in raw performance and is best suited for short-lived, latency-sensitive workloads where durability is not required.

In the next tutorial, we’ll explore AWS Glacier, a low-cost, secure cold storage solution designed for long-term archival and infrequent data access. Keep building your cloud storage expertise—we’re excited to see your progress!