Backup keywords Archiving Backups Procedures by VersionBackup Data Backups Data Loss as a Result of System Disturbance Deletion of Complete Files Deletion or Distortion of Parts of a File as a Result of Manual Operation Differential Backup Full Backup Hardware Defect (Disk or Computer) Incremental Backup Preventative Measures Against Data Loss Reasons for Data Loss Storage Space Requirements from Different Backup Methods System Backups Virus Attack

There are three different methods to continuously create backups: Full Backups, Differential Backups and Incremental Backups. Many backup systems set up the priority on Full Backups, which have to be overwritten after a short time. VersionBackup usually creates Incremental Backups. Additionally, it provides an easy-to-use management tool to view and recover the saved backup files.

If you are saving your data frequently (what you should do), your storage space requirements strongly depend on the organization of the backups. You will need very much storage space, if you copy all the data each time. It is much better to copy only the changed files and the new files.

These are the three backup types:

1. Full Backup

If you create a Full Backup, all files will be copied, regardless if they have been changed in the last time or not.

Advantage:
All the files are complete in the backup data set. They can easily be found and recovered.

Disadvantage:
If you save your data frequently, the storage space requirement will be enormous. Then you will be forced to either keep your backups only for a short time or reduce the backup frequency. Both compromises cannot be recommended.

2. Differential Backup

To use Differential Backups, you must create a Full Backup first. After this, in the following backup runs only those files will be copied, which have been changed or added since the last Full Backup.

Advantage:
You need less storage space compared to pure Full Backup saving.
For the recovery, you need only two backup data sets: the Differential Backup from the desired date and the Full Backup, which is later.

Disadvantage:
If a file has been changed once, it will be copied again and again in each Differential Backup until the next Full Backup is created. This still results in a waste of storage space.

3. Incremental Backup

An Incremental Backup includes only those files, which have been changed or added since the last backup run (not matter whether this has been an Incremental Backup or a Full Backup).

Advantage:
Each changed file will be copied only once. Therefore, the space requirements are minimal.

Disadvantage:
To keep a complete data set, you need the latest Full Backup and all Incremental Backups since then. To find one particular file, you either need a good backup management tool or work will be difficult and there is a risk of errors.

Experience from Conventional Backup Systems

If you are used to create backups professionally, you certainly know about the following basic fact:
It is extremely important to keep a clear overview over the existing backup stock.

Because only then, the effort to recover files or bigger parts of the disk will be low. Only then, the necessary safety will be realized, because you always can be sure selecting the file versions, when a recovery of a consistent state from one specified date has to be done. And only then, you will keep the overview, which backup copies are present and which one of the copies may be deleted at what time.
 

This is the reason why many system administrators follow the principle, to create only Full Backups any time when a backup has to be done. Then, all data belonging to one calendar date are stored on the same data carrier or in the same sub-section of it. This way, it is easy to recover whole directories or drives on the same version status. You only have to deal with the files of one backup copy run.

But if you use only Full Backups, you take a big disadvantage: at daily backup creation, typically 95 % of the data files or more will not be changed between two backup runs. Therefore, the Full Backups cover very much disk space, but the major portion of it really would not be needed.

”No problem,“ you might say, ”I am using tape cassettes. They provide enough storage space.
And after five days, the backups will be deleted anyway. Because I need the cassettes for the next backup run.“

But such a procedure is far away from optimum. Tape cassettes are unwieldy and expensive storage media. And they are not as safe as hard disks. Furthermore, they have file access times which we would not like to accept since 1970.

And a backup system, where the cassettes “anyway” are deleted after five days, means a significant lack of security: What will you do, if some files have to be recovered, but this will be noticed not before six days?

You can avoid these disadvantages, if you store your backups in an optimized structure on a hard disk system.
The prerequisite is that you reduce the data volume to a reasonable level. This is done, if you avoid the useless daily saving of non-changed data. Giving up the concept of daily Full Backups and introducing Incremental Backups will be an enormous improvement. You really need a Full Backup only in bigger time intervals (e.g. every two months).

Better Backup Procedure with VersionBackup

VersionBackup creates IIncremental backups to allow a high backup frequency and a long storage duration together with moderate space requirements. The problem, that you might not know, which of the Incremental Backups has to be used for any file to get a consistent recovery will be obsolete, because VersionBackup reconstructs the backups automatically. Even if the files are spread over many backups, you will receive a complete recovery matching to the desired snapshot time.

Every day, only those files are copied, which are new, which have been changed or which have a changed file name or path. This way, the backup creation will be done only in those directories, where the work has been done. But the number of Incremental Backups, which is required for the recovery, should not grow too much. Therefore, from time to time a Full Backup should be inserted. VersionBackup allows you to configure the criteria for the automatic Full Backup creation. Of course, it is also possible to request a Full Backup manually.

Deleting of the old backups will also be done automatically, keeping the consistency at any time. Because only a smaller number of files have to be copied every day, it should be possible to keep the backups for weeks or even months.

But if you want to store the backups on an external data carrier for a longer time or in an extra secure place, you should use the VersionBackup Archiving Function. The daily backups are created automatically. You have to take care only of the external archiving every two weeks e.g. As external media, we recommend USB hard disks or DVDs. Additionally, you can archive your backups to an FTP server. Even the Online Backups will be displayed, managed and used for the automatic recovery - just like all other backups.

If you archive your data to USB disks or DVDs, it is easy to keep your backups over the period of many years. Nevertheless, the overview over your backup archive will never be lost, because VersionBackup is specialized to manage the data of a very long time scale. To view into the past, you can switch the Backup-Browser’s display to a former year. If you want to recover something from that time, VersionBackup will prompt you to insert the needed data carrier.

When you changed to VersionBackup you need no compromises any more.

We will be glad, if you contact us for discussion about this topic:

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