CompTIA Server+ (SK0-005)Security and Disaster RecoveryMedium
A server administrator is implementing a new backup solution for a critical database. The requirement is to minimize the backup window as much as possible while still ensuring data integrity. Which backup type would best meet this requirement, assuming a full backup is performed weekly?
- AFull backup
- BDifferential backup
- CSnapshot backup
- DIncremental backup
Show answer & explanationAnswer & explanation
Correct answer: B. Differential backup
A differential backup copies all data that has changed since the last full backup. This results in a faster backup window than a full backup and a faster restore time than an incremental backup, as only the last full and the latest differential are needed.
Why the other options are wrong
- A. A full backup copies all data, which would maximize the backup window.
- C. A snapshot creates a point-in-time copy of data but is not typically considered a backup type in the context of minimizing backup windows for a database directly; it's often a component of a backup strategy.
- D. An incremental backup copies only data changed since the last backup (full or incremental), which has the smallest backup window but the longest restore time.
Differential Backup
A backup type that copies all data that has changed since the last full backup. It offers a balance between backup speed and restore speed.
- Copies changes since the last full backup.
- Faster to restore than incremental backups (requires only full + last differential).
- Slower to backup than incremental backups (grows in size over time until the next full backup).
Memory trick: Full is slow, Incremental is fast backup but slow restore, Differential is the balanced path.