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AWS CCP Study Guide: Storage Services

25 April 2026 · Matt

S3, EBS, EFS, Glacier, Storage Gateway, and Snowball — the full storage tier from hot to cold.

S3 — Simple Storage Service

Object storage. Files are stored as objects in buckets. No hierarchy (though key names with slashes look folder-like). Infinitely scalable, eleven 9s (99.999999999%) durability by replicating across at least 3 AZs.

  • S3 Standard: Frequent access, low latency. ~$0.023/GB/month. 3+ AZ replication.
  • S3 Intelligent-Tiering: Auto-moves objects between frequent/infrequent tiers. Small monthly monitoring fee. No retrieval fee.
  • S3 Standard-IA: Infrequent access. ~$0.0125/GB/month + $0.01/GB retrieval. Good for backups accessed occasionally.
  • S3 One Zone-IA: Single AZ, 20% cheaper than Standard-IA. Not resilient to AZ failure.
  • S3 Glacier Instant Retrieval: Millisecond retrieval, ~$0.004/GB/month. Minimum 90-day storage.
  • S3 Glacier Flexible Retrieval: Minutes to hours retrieval. ~$0.0036/GB/month. Minimum 90-day storage.
  • S3 Glacier Deep Archive: 12-hour retrieval. ~$0.00099/GB/month. Minimum 180-day storage. Cheapest storage on AWS.
Exam tip: S3 is object storage (files, images, backups). It is NOT a file system — you can't mount it like a drive. For a mountable shared filesystem, use EFS.

S3 Key Features

  • Versioning: Keeps all versions of an object. Deleting creates a delete marker; old versions remain. Enable before enabling replication.
  • Lifecycle rules: Automatically transition objects between storage classes or expire/delete them after N days.
  • Replication: CRR (Cross-Region Replication) for disaster recovery or lower latency. SRR (Same-Region Replication) for log aggregation.
  • Pre-signed URLs: Time-limited URL granting access to a private object without AWS credentials.
  • S3 Transfer Acceleration: Uses CloudFront edge locations to speed up uploads from distant users.
  • Event notifications: Trigger Lambda, SQS, or SNS on put/delete/restore events.

EBS — Elastic Block Store

Block storage volumes that attach to EC2 instances like a hard drive. Persist independently of the instance lifecycle. Tied to a single AZ — snapshots are how you migrate data across AZs.

  • gp3/gp2: General purpose SSD. Default choice for most workloads. gp3 lets you set IOPS independently of size.
  • io2/io1: Provisioned IOPS SSD. High-performance databases (up to 64,000 IOPS).
  • st1: Throughput optimised HDD. Big data, data warehouses (high throughput, low IOPS).
  • sc1: Cold HDD. Infrequently accessed data, lowest cost EBS option.

EFS — Elastic File System

Managed NFS. Multiple EC2 instances across multiple AZs can mount the same EFS filesystem simultaneously. Scales automatically (pay per GB used). More expensive than EBS (~$0.30/GB vs ~$0.08/GB) but enables shared storage. EFS One Zone is cheaper (~$0.16/GB) but single-AZ.

Storage Gateway

Hybrid storage — connects on-premises systems to AWS storage:

  • File Gateway: NFS/SMB interface backed by S3. On-prem servers write files that end up in S3.
  • Volume Gateway: iSCSI block storage backed by S3 with local caching (Cached Mode) or full local with S3 backup (Stored Mode).
  • Tape Gateway: Virtual tape library. Integrates with existing backup software (Veeam, NetBackup).

Snowball Family

Physical data transfer devices for large migrations when internet bandwidth is insufficient:

  • Snowball Edge Storage Optimised: 80 TB, ships to you, copy data, ship back. ~10 days turnaround.
  • Snowball Edge Compute Optimised: 42 TB + GPU, can run EC2 and Lambda at the edge.
  • Snowmobile: Exabyte-scale. A literal truck + container. Use for >10 PB transfers.
Exam tip: If the question involves petabytes or limited/slow internet for migration → Snowball. Ongoing hybrid on-prem to AWS → Storage Gateway. Serverless shared filesystem → EFS.