A logistics enterprise experienced a catastrophic disk failure on its core database server on Thursday at 2:00 PM. The organization operates a backup policy consisting of a full backup every Sunday at 12:00 AM, daily incremental backups every evening at 11:00 PM (Monday through Wednesday), and hourly transaction log backups taken at the top of every hour. To restore the database server to its state immediately prior to the 2:00 PM failure with zero data loss, which sequence of backup files must the systems administrator restore?
- The Sunday full backup, followed in chronological order by the Monday, Tuesday, and Wednesday incremental backups, and then each hourly transaction log backup from Thursday morning up to 1:00 PM.Answer
- BThe Sunday full backup, followed only by the Wednesday incremental backup and the hourly transaction log backups from Thursday morning up to 1:00 PM.
- CThe Sunday full backup, followed directly by the Thursday morning hourly transaction log backups up to 1:00 PM, omitting the daily incremental backups.
- DThe Wednesday incremental backup, followed by the hourly transaction log backups from Thursday morning up to 1:00 PM.
Answer
The server must be restored using the Sunday full backup, followed sequentially by the Monday, Tuesday, and Wednesday incremental backups, and completed with the hourly transaction log backups from Thursday morning up to 1:00 PM.
Because an incremental backup scheme records only data changed since the previous backup event, restoring to a specific point in time requires restoring the initial full backup first, followed by every incremental backup set generated up to the failure day in strict chronological order, and finally applying all point-in-time transaction logs recorded after the last incremental backup.
Step-by-Step Solution
Key Concept
Incremental Backup Restoration Chain vs. Differential Restoration