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Disadvantages between incremental vs differential

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I have read your descriptions of each, and don't understand if I have a crash, and need to recover files, only the differential backup scheme would make sense. My technique is to do a full backup and then do a differentials at the same intervals during the life of the files.

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Millard, please see the ATI 2016 User Guide - Basic concepts description of these different backup scheme types.

When performing any recovery operation following a disk or other crash, then you would need to have all the backup files available and then select the most recent incremental or differential file that you want to recover from.  Acronis will then identify what other files for the backup are needed and walk backwards through those files to recover all the data.

You have posted this topic in the ATI 2016 forum, hence I have been directing you to the user guide for that version, but if you have a more recent version of ATI such as 2020 or 2021, then there are changes to how both incremental and differential backups work, and greater dependencies for these files.

One key disadvantage of using differential backup files is that these will grow in size with every backup as they capture all changes to data since the initial Full backup for the task was created, so as an example, if you add 10 GB of files a day and create a new backup daily, then by the end of one week, the differential backup files will have increased significantly, i.e. by 280GB on day 7 (10 + 10x2 + 10x3 + 10x4 + 10x5 + 10x6 + 10x7)..!

Using the same example with incremental files would see only a 10GB daily increase of size as only the new, changed data since the previous backup are captured each day.
The key factor about using incremental backup files is that ALL files are required to a successful recovery, so there can be no missing files else the backup 'chain' is broken at that point and all subsequent files are rendered useless!

Note: one change for ATI 2020 / 21 is that Incremental files are now consolidated into the initial full backup file, making it less exposed to individual incremental files being deleted or damaged.  Differential files remain as separate files for 2020/21.

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Thank you.