Recovery concepts cheat sheet
RTO
Recovery Time Objective. How quickly the system must be back. Answers "how long can we be down?".
RPO
Recovery Point Objective. How much recent data the business can afford to lose. Drives backup frequency.
Full backup
A complete copy of all data. Slow to take, fast to restore. Restore needs only the most recent full.
Incremental
Backs up only data that changed since the LAST backup (full or incremental). Fastest to take, slowest to restore.
Differential
Backs up everything changed since the last FULL backup. Sits between full and incremental for speed and restore time.
3-2-1 rule
3 copies of the data, on 2 different media, with 1 copy offsite. The classic resilience guideline.
Hot site
A fully-equipped, fully-staffed standby location running the same systems live. Fastest failover, most expensive.
Warm site
Partial infrastructure ready, but data and configuration need to be brought current before use.
Cold site
An empty space with power and connectivity. Bring your own everything. Cheapest, slowest to bring up.
DRP
Disaster Recovery Plan. Focused on getting IT systems back online after a disruption.
BCP
Business Continuity Plan. Broader. Covers how the business keeps operating (people, processes) during and after a disruption.
Tabletop exercise
A walkthrough drill where the team talks through how they would execute the plan. Reveals gaps before a real disaster.