Incremental backups are one of the most popular ways to backup. They’re fast, but there’s a catch.
How incremental backup works
After an initial full backup, only changed files will be backed up. This significantly reduces the backup time since most users update less than 5% of their total data each day. The catch comes when you want to restore
Restoring an individual file from in incremental backup is as easy as selecting the restore button and the file to restore. However if you experience a full failure and need to restore everything then a restore can become time consuming. Because only changes have been backed up over time then you will need to restore from various days to ensure you get the most recent files. For example, if one file changed Thursday and the other on Friday you will need to restore from both Thursday and Friday to get the most recent version of both files.
Differential vs Incremental Backup
| Type | Benefits | Drawbacks |
| Full | Restoration is the fastest of all three types | Backup process is the slowest of all three types. Highest storage requirement. |
| Differential | Backup speed is faster than full backup.Restoration is faster than data backup with incremental In-file delta. Less storage space is need than a full backup. | Restoration is slower than data backup with full backup. Backup process is slower than incremental In-file delta backup. |
| Incremental | Backup process is fastest of all three types. Least storage space is required. |
Restoration is the slowest of all three types. Prone to data loss. |
Best Practices for Incremental Backups
It is widely recommended to perform a full backup once every week, and incremental backups the remaining days. This way you know you don’t have to go too far back to get a full restore, and it will help minimize your time in the event of a full failure. Incrementals chain the backups from one day to the next and if corruption occurs and and you get what’s called a broken delta chain is broken then you may not be able to restore everything you want.
Get the advantage of speed on your incremental backups and the safety of a sure restore by having two schedules for your backup. A full backup, maybe on a Saturday or Sunday, and incremental backups the rest of the week.
A little planning up front will reduce the potential for problems down the road.