220-1102 Question 703
Single answerGrandfather-father-son (GFS)A small accounting firm uses a grandfather-father-son (GFS) backup rotation for its file server. Daily backups are written Monday through Thursday, a weekly backup is written every Friday, and a monthly backup is written on the last business day of each month and stored offsite. On Tuesday morning, a staff member reports that a shared spreadsheet was accidentally overwritten late Wednesday of the previous week, but the issue was not noticed until now. The server itself is functioning normally. Which backup set should the technician restore first to recover the most recent usable version of the file?
- A
The monthly (grandfather) backup from the end of the previous month
- B
The weekly (father) backup from last Friday
- C
The daily (son) backup from Wednesday night of the previous week
- D
The daily (son) backup from Monday night of this week
Show answer and explanation
Correct answer: C
Explanation
Grandfather-father-son (GFS) is a backup rotation method that uses daily backups (sons), weekly backups (fathers), and monthly backups (grandfathers). In real-world recovery, the key principle is to identify when the bad change occurred and then restore from the newest backup created before that time. In this scenario, the overwrite occurred late Wednesday of the previous week, so backups taken after that point, such as last Friday's weekly backup or this week's Monday backup, would likely already contain the bad data. The Wednesday night daily backup from the previous week is therefore the best first restore point. This aligns with standard backup and recovery best practices emphasized in CompTIA A+ Core 2 objectives: use appropriate backup rotation methods, understand retention levels, and select the backup version that best meets the recovery need while minimizing data loss.
- A. Incorrect.
Incorrect. A monthly grandfather backup is designed for long-term retention and disaster recovery over longer time periods. It would likely contain a much older version of the spreadsheet than necessary. A technician should usually start with the most recent backup taken before the unwanted change, not the oldest archival copy.
- B. Incorrect.
Incorrect. The weekly father backup from last Friday was created after the spreadsheet was overwritten late Wednesday of the previous week. That means the overwritten version would most likely already be included in the Friday backup, making it a poor first choice when trying to recover the pre-incident version.
- C. Correct.
Correct. In a GFS rotation, daily son backups provide the shortest recovery point objective for routine file recovery. Because the overwrite happened late Wednesday of the previous week, the Wednesday night backup from that week is the most recent backup likely to contain the file as it existed before the accidental overwrite. Restoring from the latest backup before the incident is the standard best practice.
- D. Incorrect.
Incorrect. Monday night's son backup from this week was created several days after the overwrite occurred, so it would almost certainly contain the already-overwritten file. This option reflects a common mistake: choosing the most recent backup overall instead of the most recent backup taken before the problem occurred.