Incremental Backup: Definition, How It Works, Software to Use

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Incremental backup is a feature that analyzes your files, finds new and modified files and uploads only those files to your storage. To perform the incremental backup you need, of course, to perform an initial full backup. (Needless to say, this is one of the most efficient ways to perform your backup.)
In this article, we will talk about incremental backup, its strengths and weaknesses, and about the implementation of incremental backup in CloudBerry Backup software.

What Is Incremental Backup

As we have already mentioned, incremental backup only uploads new or modified files. Let's see how it works.

What is incremental backup? How incremental backup works?

Imagine that you have five files for backup and you are going to run weekly backup.
  • The first-week backup (initial full backup) will include all of them.
The second week, file1, file3 and file4 have been modified.
  • The second-week backup will only copy your modified files: file1m, file3m, file4m.
The following week, file2 and file5 have been modified. They become file2m and file5m.
  • The third-week backup will only copy your modified files file2m and file5m.
In the end, you have a dataset with several files completely changed. Each week, only the modified files were uploaded.

That is how incremental backup essentially works. And if a file is not changed but added to the backup set after week 3, it will appear in week 4 as file6. 

The Advantages of Incremental Backup

There are specific advantages to performing incremental backups compared to full backups. They are:

  • Faster backups. Incremental backup will upload only changed and new files in the cloud or local storage. This is considerably faster than uploading an entire dataset each time.
  • Less storage capacity needed. Storage space means money. The less storage space you need, the less you will pay to your cloud storage provider. If you perform local backup, you will spend less on your hard drives.
  • Less bandwidth is consumed. When you perform a backup, the last thing you want is for it to cause your Internet connection to hang.

The Disadvantages of Incremental Backup

It should be said that Incremental backup is good, but not perfect. The main disadvantage of incremental backup is that the backup grows until the next full backup is done. In other words, incremental backup only performs comparisons to the previous backup. For example, if you perform incremental backups for one year, without any additional full backups or retention rules set to your files, you will have a year’s amount of data. All files that were deleted on your local device since the first full backup remain in your storage. To prevent that from happening, you should:

  • Perform full backups from time to time. When you perform a full backup, you break the sequence of the previous incremental backups. In other words, you will backup only the files that currently exist on your device; the incremental backup only adds new files and changes since that last full backup.
  • Set a retention policy for your files. Retention policy allows you to choose how long you keep your old files and how many versions of each file you keep. With incremental backup, it’s recommended to set a policy that allows you to delete old files after a given time, or files that have been deleted from your device. 

Incremental Backup Software

CloudBerry Backup fully supports the concept of incremental backup, both locally and to the cloud, and enhances it with additional features. Our software performs incremental backup by default to ensure that there are no unnecessary copies of files and your storage space is used wisely.

However, depending on your needs, an incremental backup may not be enough — and you may want to look at an option called block-level incremental backup.

Block-Level Incremental Backup

Block-level backup performs in-depth file analysis and backs up only the modified portions of files, which makes it  an efficient tool when used properly.

This functionality is featured in CloudBerry Backup and can be easily toggled from the UI of the software by going to the Backup Plan Wizard, then Advanced Settings.

Block level incremental backup software - CloudBerry Backup Advanced Options screenshot

Check out our blog article about block-level backup if you want to know more about its architecture and its implementation within CloudBerry Backup.

Point-in-Time Recovery from Incremental Backup

If you use incremental backup and have configured your backup plan well, then you will be able to recover your data, when needed, to the chosen point in time.

As an example, let’s say that your computer has been hit with ransomware. Luckily, your backup software has uploaded all your files to the cloud, and you can simply recover your files to the state of the previous week or point in time when your files were not affected by ransomware.

Final Word

Incremental backup is an incredibly helpful feature. However, backups should be carefully planned if you want it to be truly efficient. Create an appropriate retention plan, plan the usage of block-level incremental backup, and plan the scheduling of your full backups. Planning is the key to the safety of your data, and keeping your storage budget in line.

Bonus Video

Be sure to check out our new video format—One Minute Drill. In our first video, we will explain the basics of incremental backup in (roughly) one minute. If you like this video, there will be much more to come. Let us know which topics will be most interesting to you.