A differential backup is a kind of data backup which preserves only the differences between the current file system and previous full backup, saving only the gap in the existing data as the final copy. The differential backup does not save the changes to the entire file system, as some people believe it to be the case. The differential backup only saves the differential and not the entire file system. This kind of backup is very useful for businesses, where multiple file systems might exist and many computers might be linked together.
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The differential backup starts by creating a mirror of the whole file system. It then merges all changes into the main backup. The incremental backup then follows. When the differential backup has finished saving all the changes in its mirror, the incremental backup starts by restoring only those files which have been changed since the last copy. If any changes are missing, they are automatically restored along with the rest of the files in the mirror.
There are a number of reasons why companies make use of differential backups. They include the probability that a single day's activity could damage several important files, and the probability that a disaster may strike the company's entire network within a few hours of the initial failure. Most companies make use of differential backups to protect against these possibilities. One drawback of the differential backup, however, is that when a single of them causes a failure, the other backups also fail.
The advantages of differential backups are many. They are designed to store an extended version of the files on the same disk as the primary files. This is done so that in the event of a crash, the backup will contain the data pertinent to all the individual files. Another advantage is that this kind of backup can be initiated before any other kinds of backup are taken, meaning that the files won't need to wait until the others have been copied. This means that the differential backup will take care of the crucial files first, allowing time for other types of recovery.
In addition, differential backups allow you to recover specific files at a time. This is especially useful if a hard drive fails and you cannot access a number of important files on it. In addition, differential backups allow you to restore specific files or parts of a file or program. For example, you can make a copy of your entire database in case you discover that a corrupt disk has caused it to crash.
There are some disadvantages of making use of a differential backup, as well. The biggest problem is that it requires the creation of a backup copy, just like any other backup, which makes it susceptible to human error. Furthermore, differential backup files contain information about where the file is saved and which version exists at any given time. If a user makes changes to the program without saving the file to the correct location, the backup will not be able to recover the changed portions of the file because they were not saved in the right location.
Another problem with differential backup is that it does not provide protection against disaster. Most people will not want to spend their time creating a backup for every folder and file in their entire system. If something happens to the server, you still have to get the files from whatever source. If they are not in the differential backup, you may find yourself losing data due to inaccessible files. It is far more secure to simply create a full backup and save the differential copy as a back up for the files that you need to access frequently.
There are many benefits to using a differential backup. However, it is not advisable for everyone to use it. There are risks of losing data due to human error as well as to natural disasters. Also, it can take up a lot of time and effort to maintain. If you do not regularly create and save a full backup, it is better to simply avoid making use of a differential backup altogether.