Bitlooker feature was introduced in Veeam Backup & Replication few years ago. it is a the feature used to fine tune and optimize the veeam backup storage size. Bitlooker is a patent-pending data protection technology from Veeam.
“The first part of BitLooker was introduced in Veeam Backup & Replication back a few years ago and enabled the exclusion of the swap file blocks from processing. Considering that each VM creates a swap file, which is usually at least 2 GB in size and changes daily, this is a considerable amount of data that noticeably affects full and incremental backup size. However, BitLooker automatically detects the swap file location and determines the blocks backing it in the corresponding VMDK. These blocks are then automatically excluded from processing, replaced with zeroed blocks in the target image and are not stored in a backup file or transferred to a replica image.”
In Veeam Backup & Replication version 9 the bitlooker capabilities have extended with below features.
- Excluding swap and hibernation files blocks
- Excluding deleted files blocks
- Excluding user-specified files and folders
The user specified files/folders can be application logs, application caches, temporary files, personal files etc.
Below screenshot shows the option to configure the Exclude Swap file blocked and Exclude deleted file blocked. By default these features are turned on.
This option can be enabled by editing the backup job> Storage window>Advanced> Then storage tab.
Below screenshot shows the option to configure the File and Folder exclusions. This can be configured by editing a Backup job>Guest Processing Window> Enable Application Aware Processing> Applications Button>Select the desired VM and Edit.
Bitlooker feature may not give a good impact if you configure it on the on-premise backup jobs, however if you are doing virtual machine replication for large file servers and lot of file servers then by enabling this feature will help to reduce the replication window and reduce the disk size on the DR side (Especially helps to reduce the disk usage if you have a managed DR where your disk usage costs money)