CompTIA Security+ (SY0-701)Security OperationsHard
A database administrator performs a full backup of a critical server every Sunday at midnight. On each subsequent day of the week, a backup job runs that captures only the data changed since the previous day's backup. On Thursday, the server fails and must be restored. How many backup sets must the administrator restore to fully recover the data?
- A4 — Monday through Thursday's backups only
- B2 — Sunday's full backup and Thursday's backup
- C1 — only Thursday's backup
- D5 — Sunday's full backup plus Monday through Thursday's backups
Show answer & explanationAnswer & explanation
Correct answer: D. 5 — Sunday's full backup plus Monday through Thursday's backups
This describes an incremental backup scheme, where each day's backup only contains changes since the previous day. To restore, the administrator must apply the full backup plus every incremental backup in sequence up to the point of failure: Sunday (full), Monday, Tuesday, Wednesday, and Thursday (four incrementals), totaling 5 backup sets.
Why the other options are wrong
- A. Skipping Sunday's full backup would omit the baseline data entirely.
- B. This would work for differential backups, but incrementals require every day in sequence, not just the last one.
- C. Restoring only Thursday's incremental would miss all data from Sunday through Wednesday.
Incremental Backup Restoration
A backup strategy that captures only data changed since the last backup (full or incremental); restoration requires the last full backup plus every incremental in sequence.
- Incremental: smaller, faster backups but slower, multi-step restore
- Differential: backs up changes since last full backup; restore needs only full + latest differential
- Full backup captures entire dataset every time, largest but simplest restore
Memory trick: Incremental = climbing every stair one at a time to reach the top.