NovaBACKUP Security Blog

What is the Difference Between File Backup and Image Backup?

The whole backup and data protection space is filled with a lot of nomenclatures that if you do not already know the abbreviations, the specific words and phrases that are used, or concepts you can become lost very easily.  In this article, I am going to go over two concepts that seem to come up all the time in NovaBACKUP’s Technical Support discussions with customers or prospective customers.  These two are the difference between file-level and disk image backup.

File Backup

What is a Disk Image Backup?

An image backup is simply an image or copy of your entire system, including your operating system. A disk image backup, can be called a number of different names such as: bare metal backup / recovery (BMR), disaster recovery backup, ghost backup, image-level backup, block-level backup, system image recovery, or a clone of your machine.  This is a very simple way to configure backups where you just select an entire drive, partition, or an entire machine, which typically backs up the entire selection you have selected. 

Some backup software solutions such as NovaBACKUP, allow you to backup changes since the last full disaster recovery backup.  Where disk image backups really shine is in a complete disaster type of situation.  For instance, when your hard drive dies, your Windows will not boot or is corrupt, your machine is stolen, an upgrade goes horribly wrong, or another major disaster that requires a complete rollback of the entire system and then perform a system image recovery.  While most disk image backup products, NovaBACKUP included, can access single files from the disk image backup in case of the need to restore a single file, file backup is more suited to file-level restores.

What is a File Backup?

A file backup, or file-level backup is the most common type of backup out there, and for good reason.  A file backup is very simple to understand and very simple to make sure they are good.  File backups basically come down to you selecting some files and folders that you want to back up and then where you want those file-level backups to go.  File-level type of backups typically allow for more granular options for backup and restore of things such as Exchange, SQL, System State (Registry, Active Directory, and other things), along with the ability to exclude a lot of other things that you probably do not want to backup unlike most disk image backups.  If you were to compare a file backup vs image backup, you would find that file backups are typically a more flexible way of doing backups, scheduling, and are normally smaller backups than disk image backups. But, image backups are better in disaster scenarios where an entire system restore is required.

What Type of Backup is Recommended?

Now that you a rough idea of the difference between file backup vs image backup, you may be wondering which backup type should you use?  I would suggest you use both types. 

A good, typical backup setup would include:

  1. A disk image backup (disaster recovery) once a month
  2. A full file-level backup once a week
  3. A differential file backup (backup that backs up all files since the last full file-level backup) every day other than the full backup day. 

This type of schedule will give you an easy quick way to get files and folders back, which is where a majority of the restores we see happen, along with giving you a good disk image base while being backup space conscious. 

I would also suggest that before any major change to the machine that you are backing up to, do a manual disk image backup.  This can include service packs to production-type software such as Exchange, SQL, or other software that is critical to your business, new hardware, or installation of new software.  That way if something goes wrong with that change you can bring the machine back to where it was before the change very quickly. 

While many of these recommendations are just my opinion based on my years of experience working with clients in the backup space, you should make any adjustments to fit your business needs. Creating a backup file using these backup recommendations are very easy to setup within NovaBACKUP, and will provide you with great data protection against loss.  If you happen to be utilizing another type of backup software that does not include both disk image and file backup capabilities in it, it might be worth reevaluating the software you are using and to look at the downtime you are willing to accept when something happens and how much that will cost you.