What is an EBS snapshot archive?
EBS Snapshot Archive is a low-cost storage tier for EBS snapshots that you need to retain for compliance or long-term backup purposes but rarely or never need to restore. Archived snapshots cost up to 75% less than standard snapshots but require 24 to 72 hours to restore before they can be used.
By default, all EBS snapshots are stored in a standard tier that allows fast restoration (within minutes). However, for snapshots that need to be kept for regulatory compliance, auditing, or long-term archival purposes — and are unlikely to ever be needed for quick restoration — storing them in the archive tier dramatically reduces cost. The tradeoff is a retrieval window of 24–72 hours before the snapshot can be used.
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Standard Tier — Fast restore (minutes), higher cost (~$0.05 per GB-month), for frequently needed snapshots
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Archive Tier — Slow restore (24–72 hours), 75% cheaper (~$0.0125 per GB-month), for rarely-accessed snapshots
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Minimum archive duration — 90 days. If you delete or restore a snapshot before 90 days, you are still charged for 90 days.
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Storage format — Archived snapshots are stored as full snapshots (not incremental), so they are self-contained and do not depend on a snapshot chain
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Encryption — Archived snapshots retain the same encryption settings as the original standard-tier snapshot
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Compliance and regulatory requirements that mandate keeping backups for years (HIPAA, PCI-DSS, SOX)
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Year-end or quarterly audit snapshots that must be retained but rarely accessed
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Long-term disaster recovery copies that serve as a last resort restore point
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Snapshots older than 90 days that have never been used for restoration
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Cost optimization — archiving old incremental snapshots that are part of a long backup chain
Scenario Questions
0-2 years experience
- 1You need to back up a 500 GB EBS volume but want to keep the backup for only a few months to save cost. How would you use an EBS snapshot archive in this scenario?
- 2If you create a standard EBS snapshot and then archive it, what changes in terms of storage class and cost?
2-5 years experience
- 1Our application experienced a sudden spike in storage costs after we started archiving snapshots. Walk me through how you would investigate why the costs increased.
- 2We have a nightly backup pipeline that creates snapshots and archives them after 30 days. One day the restore of an archived snapshot fails with a timeout. What could be causing this, and how would you fix it?
- 3Explain the trade‑offs between keeping snapshots in the standard tier versus archiving them for a compliance‑driven data retention policy.
5-8 years experience
- 1Design a backup retention strategy for a fleet of 200 TB of EBS volumes that must retain daily backups for 7 days, weekly for 4 weeks, and monthly for 2 years, using snapshot archiving to control cost. What lifecycle policies would you set up and why?
- 2Our disaster‑recovery process requires restoring a volume from an archived snapshot within 2 hours, but archived snapshots typically take longer to retrieve. How would you architect the system to meet the SLA while still benefiting from archive cost savings?
- 3During a large‑scale migration, we need to move billions of snapshots to archive storage. What challenges might you encounter with AWS API limits, billing, and data integrity, and how would you mitigate them?
8+ years experience
- 1At a company‑wide level, we are revisiting our data‑retention policies to align with new regulatory requirements that mandate 7‑year storage of certain logs. How would you incorporate EBS snapshot archiving into a cross‑team strategy, considering cost, access patterns, and auditability?
- 2We have multiple AWS accounts and a centralized backup account that stores archived snapshots. Describe the architecture and governance model you would implement to ensure secure, auditable access and consistent lifecycle management across teams.
- 3Looking ahead, how would you evaluate whether to keep using EBS snapshot archiving versus moving to a purpose‑built archival service like Amazon S3 Glacier Deep Archive for long‑term storage, considering factors such as restore latency, cost, and operational complexity?
Follow-up Questions
- What impact does archiving have on snapshot restore times?
- How does the pricing model differ between standard and archived snapshots?
- Can you delete an archived snapshot directly, or must you restore it first?