Backup Strategies: 3-2-1 and Automation

Backups are only worth something when the restore works. The 3-2-1 rule is the gold standard.

The 3-2-1 rule

• 3 copies of the data (production + 2 backups).
• 2 different media (local + external/cloud).
• 1 copy offsite (different location).

Backup types

• Full backup: everything — slow, but simple restore.
• Incremental: only changes since the last backup — fast, but restore chain.
• Differential: changes since the last full — middle ground.

Automation

restic, borgbackup, restic + rclone for cloud, or managed services. Important: exclude rules, retention policy and encrypted backups.

Restore tests

Practice a restore regularly (e.g. monthly) in a VM or staging environment. Untested backups are wishful thinking.

Monitoring

Monitor backup jobs (exit codes, logs, alerting). A silent failure for months is the most common backup failure.

See also: System Administration.