Per-VM backup files and deduplication

[JoshuaPostSAMC]

If Per-VM backup files are enabled on a repository, is deduplication for that particular VM disabled, or should it still work, but only in the scope of that VM instead of the entire job?

I had a large file server with 3 TB of data and I created a new drive letter and did a robocopy to move all data from one drive to the new drive, including all security identifiers, and when Veeam ran, it increased the forward forever incremental file by hundreds of GB as the copy continued until everything was done and then the incrementals went back to 8-12 GB each time it ran.

I would have expected deduplication in scope of this single VM to still be active and not have a significant increase as the files are the exact same, but this does not appear to be the case. Is this intentional or indicative of an issue?

[DGrinev]

Hi Joshua,

You are right, it will work only for the separate full backup files of each VM.
Incremental files contain only changed data blocks compared to previous run, so deduplication will not work as there's no similar blocks to have dedupe between them.
Please review existing thread for detailed information.

Thanks!