backup-and-disaster-recovery

1# Backup and Disaster Recovery
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3Plan for the worst case: the database is gone, the host is down for a week, the deploy was poisoned, ransomware encrypted everything. The skill is in advance preparation, not reaction.
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7## When to use
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9- Setting up backups for a new system
10- Reviewing and validating backup architecture
11- Defining RPO (recovery point objective) and RTO (recovery time objective)
12- Running a disaster recovery drill
13- Diagnosing gaps after an incident
14- Planning for ransomware, data corruption, or insider threats
15- Migrating to a new platform (DR planning belongs in the migration plan)
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17## When NOT to use
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19- Active incident response (use `incident-response`)
20- Routine deploy rollbacks (use `launch-runbook`)
21- Code or content versioning (covered by Git, CMS revision history)
22- Routine database snapshots (use this skill to set them up; routine review goes in monitoring)
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26## Required inputs
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28- The systems in scope (databases, file storage, code, configs, secrets)
29- The hosting platforms and providers
30- Existing backup tooling and what it covers
31- Tolerance for data loss (in time)
32- Tolerance for downtime (in time)
33- Compliance requirements (some regulations mandate specific backup standards)
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37## The framework: 4 questions
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39Every disaster recovery plan answers four questions explicitly.
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41### Question 1: What needs to be recoverable?
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43List every system that holds state. Categorize by criticality.
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