What does a solid backup strategy look like?

Question

Accepted Answer

A solid backup strategy is more than scheduling a dump. I start from the 3-2-1 rule: at least three copies of the data, on two different media or storage types, with at least one copy offsite, in a different region or even a different provider, so that no single failure, a disk, a data center, an account, takes out both production and the backups. The single most important and most neglected practice is testing restores: an untested backup is not a backup, it is a hope, because backups fail silently, corrupt, incomplete, missing a critical table, and you do not want to discover that during an actual disaster. So I regularly perform real restores to verify they work end to end and to measure how long a restore actually takes, which is my real RTO. I also make backups immutable, write-once-read-many, or air-gapped, so that ransomware or a compromised admin account cannot delete or encrypt the backups along with production, which is exactly the failure mode that has destroyed companies, their backups were reachable from the same access that got compromised. And I automate the whole thing and monitor that backups are actually succeeding, because a silently-failing backup job is worse than none since it gives false confidence, and I set the frequency and retention to meet the business RPO, how much data loss is acceptable, and RTO, how fast I must be back. So 3-2-1, tested restores, immutable copies, automation with monitoring, and alignment to RPO and RTO.

Answer

Why is testing restores the most important part?

Backups fail silently (corrupt, incomplete, misconfigured). If you never restore, you only find out during a real disaster, when it is too late. Regular test restores prove they work and measure your true RTO.

Answer

How do immutable backups protect against ransomware?

WORM/air-gapped backups cannot be deleted or encrypted, even by a compromised account, so the attacker cannot destroy your recovery path along with production. Reachable, mutable backups can be encrypted in the same attack.

What does a solid backup strategy look like?

What does a solid backup strategy look like?

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