220-1102 Question 695
Single answerSynthetic fullA small business backs up its accounting server to a disk-based backup appliance every night. The backup application is configured to take one full backup on Sunday and incremental backups Monday through Friday. On Saturday, the administrator wants to create a new full backup file on the backup appliance for faster restores, but the WAN link to the branch office is congested and cannot handle retransmitting all server data. Which backup method should the administrator use?
- A
Synthetic full backup
- B
Differential backup
- C
Snapshot backup
- D
Copy backup
Show answer and explanation
Correct answer: A
Explanation
The best answer is synthetic full backup because it is specifically designed to create a new full backup using backup data that already exists on the backup storage target, typically by combining a previous full backup with later incremental backups. In practice, this reduces load on the production server and minimizes network usage, which is why it is well suited for remote offices or bandwidth-constrained links. By contrast, differential and copy backups still require reading data from the source system, and snapshots are a different recovery technology rather than a backup-chain consolidation method. This aligns with common enterprise backup best practices and vendor documentation from major backup platforms, which describe synthetic fulls as a way to improve restore speed while reducing backup window and network impact.
- A. Correct.
Correct. A synthetic full backup creates a new full backup from an existing full backup plus subsequent incremental backups that are already stored on the backup repository. This avoids reading all data again from the protected server and avoids sending the full dataset across the network, making it ideal when bandwidth is limited but a current full backup file is needed for faster restore operations.
- B. Incorrect.
Incorrect. A differential backup would back up all changes since the last full backup, which would still require transferring changed data from the server to the backup system. It does not build a new full backup from existing backup files already on the repository, so it does not best address the requirement to avoid retransmitting data across the WAN.
- C. Incorrect.
Incorrect. A snapshot captures the state of a system or volume at a point in time, often for quick rollback or short-term recovery, but it is not the same as creating a synthesized full backup set from previous backups. Snapshots also commonly depend on the underlying storage platform and may not reduce WAN usage in the way described.
- D. Incorrect.
Incorrect. A copy backup creates an additional backup copy without affecting the normal backup chain, but it still involves backing up data from the source system. It does not merge an existing full backup and incrementals on the backup appliance into a new full backup, so it does not meet the stated network constraint as effectively as a synthetic full.