Data protection has turned to be of everyone’s concern, every day there are data losses happening around the world.
What is Data Backup?
Data backup is a process of taking a copy or duplicating the data to allow recovery of the duplicated set after an event of data loss. Data backup can ensure data protection and there are different methods of data backups.
In this blog, I will explain the backup types/methods and their advantages.
- Full Backup
- Incremental Backup
- Differential Backup
- Synthetic Backup
- Incremental forever Backup
In the above-listed types of backup, the full, incremental and differential backups are basic types that everyone must have heard about, but the synthetic and incremental forever backups are two new types to the data backup market. Apart from the above-said types, there are various types such as mirror backup, reverse incremental backup and continuous backup.
Continue reading to know about these 5 different types, 3 variations of it and find out which one will suit your environment.
A full backup is a complete copy of the data you’ve configured for backup. But the firms can only periodically use this back up since it is more resource consuming.
Consider you want to take a backup of 2TB data and store it in a 10 TB storage device. If I perform a full backup on a daily basis (for 5 days), then I can store only 3 or 4 full backups.
I can understand your question, if it is 2TB of backup data and storage is 10 TB then I must have logically 5 days of full backups. Here, 2TB of data can have changes happening in it on a daily basis. Initially, it is 2 TB and on the next day, if I add files or make changes, this will lead to the addition of 0.5 TB to the initial 2TB so now I have 2.5 TB.
In this scenario, the backup and restore process will take a long time to complete and you will also need a larger storage resource. You can carry this type of backup on a weekly/monthly basis.
To overcome the disadvantages of full backups, the concept of Incremental backups were introduced.
This decreases the resource consumption by backing up only the changed data since the previous backup.
For example, suppose you’ve configured a full backup on Monday and then incremental for the rest of the week. Now, Tuesday’s backup will contain the data that has changed since Monday. Wednesday’s backup will contain the data that has changed since Tuesday, and so on.
With this, you have less utilization of time and storage.
But we also have a disadvantage using incremental backup during the restore process. If I have to restore the backup data from Wednesday, then I have to first restore Monday’s full backup and then Tuesday’s incremental backup along with Wednesday’s incremental, which is time-consuming.
Differential backup lets you back up the changed data since the last full backup.
Difference between Incremental Backup and Differential Backup
There is always a misconception between incremental backup and differential backup. To sum up, the differential backup includes all the changed data since the last full backup whereas Incremental backup includes all the changed data since the previous backup.
Differential backup – example: If you’ve configured a full backup on Monday and differential backups for the rest of the week then, Tuesday’s backup will be the changes made since the full backup on Monday. Wednesday’s backup will include the changed data since Monday.
The differential backup ensures shorter restore time when compared to an incremental backup, but the restore time can vary i.e, will become large if the data size increases.
Synthetic full backup
A synthetic full backup takes a full backup and combines following incremental to provide a complete full backup. The synthetic full backup is stored aside and then incremental are performed.
A synthetic full backup has an advantage over other backup types i.e. it is easy to restore when compared to incremental backup and differential backup and also reduces the resource utilization.
Incremental backup Type – Forever Incremental
Incremental forever backups are similar to the normal incremental backup. The backup process begins by taking a full backup and after that, only incremental backups are performed forever.
The difference between the normal incremental and the incremental forever backup is the availability of the data for a longer strand where you can have more recovery points to restore.
The mirror backup is similar to a full backup, as the name suggests it’s an exact copy of the source data.
Mirror backup stores only the latest file version in the destination and files are stored separately alike source. This lets you access the files directly without having to perform the restore. Hence, it is considered to be the fastest backup method as the data is not compressed/encrypted into a single file at the destination.
Though being the fastest backup method it gives you a major setback, since it is just the exact copy of data made without compression it eats up more of your storage space. And, another major drawback of the mirror backup is that it holds no track of previous versions of the backup data.
Reverse Incremental backup
As Incremental backup, this reverse incremental backup initially takes a full backup and captures only the changes as incremental backups, but these incremental backups are injected reversibly into the full backup, thus making it as the latest version of the complete full backup. This reverse incremental backup is more propitious since it ensures more swift recovery as it contains the latest version of the complete full backup.
The reverse incremental backup is favorable than an incremental backup, since if one increment gets corrupted then the process of restore is highly questionable; whereas in reverse incremental backup, all the increment merge with the full backup giving you a complete one point restore.
Continuous Backup is also referred to as “real-time backup” as it backs up whenever a change is made.
All the previous backup types run on a periodic basis whereas continuous backup monitors the file on a real-time basis and backs up as soon as a change takes place on the file.
The initial backup will be a full backup and successive backups are incremental that will take place only when a change occurs.
This type of backup can be chosen if you want to have continuous data protection to enable business continuity.
Which Backup method should you choose?
As you can see, all the above-mentioned backup types are useful based on your requirement.
Backup software should provide various backup types to stand as an unique backup solution.
Vembu BDR Suite is one such solution that provides various data backup types to protect diverse IT environments that include physical, virtual and cloud – SaaS apps from one strand. As far as Vembu BDR is concerned the initial backup is always a full backup followed by the incrementals, this is because the Vembu BDR tracks all the changes using CBT (Changed Block Tracking) technology; Additional full backups can also be taken optionally.
In file/folder level backup of Vembu BDR, continuous backup option is availed, so whenever there happens to be a change in the data the backup will be automatically triggered.
There are other backup types which Vembu supports, you can see for yourself the functions of different types of data backups by downloading the Free Trial Version of the software for 30 days!