Enabling variable-length deduplication (VLD) algorithm for universal shares
The deduplication engine breaks the backup image into the segments and compares the segments to all of the segments that are stored in that deduplication node. Only the unique segments are sent to the NetBackup Deduplication Engine on the storage server. The Deduplication Engine writes the data to a Media Server Deduplication Pool.
See About variable-length deduplication on NetBackup clients.
NetBackup Deduplication Engine provides a couple of variable-length deduplication algorithm types. It brings better deduplication ratio if you use one variable-length deduplication algorithm for universal shares.
The variable-length deduplication algorithm is not enabled by default for universal shares. Use the vpfs_actions command-line utility to see the current configuration.
To configure the variable-length deduplication algorithm for universal shares
- Navigate to the following location on the media server:
/usr/openv/pdde/vpfs/bin/ - Run the following command to check the current configuration:
/usr/openv/pdde/vpfs/bin/vpfs_actions -a tune --imageId <share_id>
Sample output:
segment_type: "vld" applications: [{"type": "vld", "sw_min": 16, "sw_max": 32}] status: 0 - Configure the variable-length deduplication version.
/usr/openv/pdde/vpfs/bin/vpfs_actions -a tune --imageId <share_id> --segment <VLD-version> --sw_min <sw_min> --sw_max <sw_max>
Note:
For the new environment where image backups do not exist in the storage, universal share automatically uses VLD v2 instead of VLD when you specify -segment VLD in the first-time configuration.
Option | Description |
|---|---|
imageId | Unique identifier for the image. |
segment |
|
sw_min | The minimum segment size (KB) of the segmentation range (16 - 127). Suggested values are 16, 32, and 64. |
sw_max | The maximum segment size (KB) of the segmentation range (17 - 128), this value must be greater than sw_min. Suggested values are 32, 64, and 128. |