Backup with Veeam

It is very important to test a backup. Untested backups are unreliable. This also applies to disaster recovery plans. All this, of course, to avoid stress in the event of the loss of an important resource. The various tests must be carried out at regular intervals.

Active Full

This type of backup is also known as a full backup. Data is stored in a file with the extension vbk An Active Full backup can be run regularly (weekly, for example). This is to replace an older Active Full backup. With this type of backup, the backup chain is reset. Incremental backup files use this backup as the starting point for restoration. This type of backup is subject to the retention rule.

Synthetic Full Backup

The use of a full backup, or Active Full, means that you have the complete backed-up resource at any given time. They are, however, rather greedy for storage space. This has an impact not only on the network, but also on storage space. Synthetic full backups also offer the advantage of containing all the data of the backed-up resource(s). It does, however, offer more optimized data recovery.

When performing an Active Full backup, Veeam Backup & Replication recovers data from the source (source datastore for the VM, for example). Compression and deduplication are performed before writing to the VBK file. With a synthetic backup, data is not recovered from the source. The data in the backup repository is synthesized (using full backup – vbk file and incremental backup – VIB file). The data in the backup repository is synthesized. The data is consolidated and the vbk file created.

This type of backup offers significant performance benefits. By not calling on production resources, potential disruption to production is avoided. Synthetic full also resets the backup chain. The VBK file is used as a new starting point for incremental backups. This type of backup is subject to the retention policy.

Forward incremental

Using this backup mode, Veeam Backup & Replication creates several types of files. The backup chain is made up of several VBK files (full backup) and VIB files (incremental backup).VBK files created during the execution of a full backup can be created using an active full or synthetic full backup. The number of VIB files depends on the number of full backups. With one full backup per week, the number of .vib files is six. With two full backups per week, the number of .vib files is greatly reduced (see diagram below).

Full backup on Sunday

Full backup on Wednesdays and Sundays.

This backup method requires more storage space. The backup chain may contain one or more full backups. It is worth noting that Veeam Backup & Replication can store more restore points than the number defined in the retention policy.

Reverse incremental

With this type of backup, several reverse incremental backup files (VRB) and one full backup file (VBK) are used. Note that VRB files precede VBK files in the backup chain.

Veeam Backup & Replication deletes VRB files when the retention time is exceeded. This backup method obviously has an impact on storage. During backup, Veeam Backup & Replication injects the modified data blocks into the VBK. A VRB file is also created. This contains only the oldest data. In this way, the different VRB files enable different restore points to be used. Note that the most recent restore point can be restored using the VBK file (full backup).