Snapshot vs Backup — When to use which

Iris Li

Quick reminder

Snapshot = a point-in-time delta tied to the original disk/state. Good for short-term rollbacks.
Backup = an independent copy (full/incremental) stored separately. Good for long-term retention & disaster recovery.

When to use a snapshot (short & temporary)

Before config changes, OS/app updates, or risky experiments.
For development/testing where you need fast rollback.
Keep snapshots short-lived (hours → days), not as durable protection.

When to use a backup (reliable & long-term)

Production protection: compliance, long retention, site failover.
For migrations, hardware changes, or recoveries after storage failure.
For point-in-time restores and offsite disaster recovery.

Practical rules (must-read)

Don’t treat snapshots as backups. Snapshots depend on the original storage — if that storage fails, snapshots are gone.
Limit snapshot lifespan & chain length. Long snapshot chains slow I/O and increase storage use. Aim to delete within 24–72 hours.
Store backups off-host or off-site. Use remote object storage (S3/Wasabi) or a different datacenter/PBS.
Ensure application consistency. Use app-consistent methods for DBs (VSS, freeze/wal shipping, logical dumps), not only FS-level snapshots.

Landon Fairfax

Backups also give you geographic separation. Snapshots can’t protect against datacenter outages or ransomware hitting the storage layer — offsite copies can.

Sylas Beaumont

Snapshots for testing/rollback, backups for compliance and offsite recovery. Saved and appreciated!

Adrian Prescott

Thanks for sharing! Fully agree that “snapshots are not backups” — we once lost all snapshots in a storage failure; painful lesson.

Quentin

Keep backups offsite (S3/Wasabi or a remote PBS) to protect against datacenter-level failures. Thanks!

Tobias Whitmore

👍 Solid breakdown! A lot of people confuse snapshots with backups, but they’re not the same at all. We once relied only on snapshots, and when the host disk failed, every snapshot vanished with it 😅. Now we just use snapshots for short testing, but for real protection it’s always offsite backups—way more peace of mind.