What is the BEST backup strategy for changing files only, considering time constraints?

The best backup strategy for changing files only, particularly when considering time constraints, is the differential backup. This method focuses on backing up only the data that has changed since the last full backup. As a result, each differential backup contains all the changes made since the last full backup, which makes recovery straightforward. When you need to restore data, you only need the last full backup and the most recent differential backup.

This approach is more time-efficient than performing a full backup every time, which would require significantly more storage space and time to complete. Additionally, unlike incremental backups, which require the restoration of multiple sets of data (the last full backup and all subsequent incremental backups), differential backups simplify the recovery process, requiring fewer steps in case of data loss.

Snapshot and full backups have their roles but do not provide the same balance of efficiency and simplicity in restoring only the changed files when faced with time constraints. Thus, for a strategy that prioritizes both the need to back up changing files and the limitations of time, differential backup stands out as the optimal choice.