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Backup

Backups are a core defence against data loss and ransomware. This page explains the 3-2-1 rule, offline and immutable backups, restore tests and common mistakes.

Who this page is for

IT leaders, administrators, executives of smaller companies and anyone who wants an honest view of their recovery capability.

Why backups matter

Backups are often the last line of defence. With ransomware, hardware failure, accidental deletion or misconfiguration they decide whether an incident is resolved in hours or weeks.

The 3-2-1 rule

Three copies of the data on two different media, with one off-site. The rule is old but still solid and can be extended by an extra offline or immutable copy.

Offline and immutable backups

Offline backups are physically or logically disconnected from production after writing.

Immutable backups protect copies against change and deletion for a defined retention. Both make backups much more resistant to ransomware.

Restore tests

A backup never restored is not a proven backup. Regular restore tests verify that data can be brought back within an acceptable window. Only a successful restore proves real resilience.

Backups are not a substitute for prevention

Relying on backups alone means costly recovery with long downtime. Prevention through MFA, patch management and awareness reduces incidents materially.

Checklist

  • 3-2-1 rule or better in place
  • At least one copy offline or immutable
  • Backup accounts separate from production directory
  • Regular restore tests with documented results
  • RTO and RPO defined
  • Backups integrated into incident response plan

Frequently asked questions

+How often should restores be tested?

At least yearly, more often for critical systems. Documenting the outcome matters.

+Are cloud snapshots enough?

They help but do not replace real backups. Anyone who compromises the same tenant can often delete snapshots too.

+Where should backups live?

In a different location and security context than production. Otherwise they share the impact of an incident.

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