When a backup starts, the client loads the Exclude List into working memory. As it backs up files and volulmes, each object is compared to the Exclude List held in memory. As files are read off the disk during the backup, If a file fits an exclusion, it is not passed onto the Media Server ... it is skipped.
Due to the nature of how NetBackup handles excluding Virtual Disks (.vhd files) we must communicate with the Virtual Disk service when loading Exclude Lists into memory.
Communicating with the Virtual Disk environment may depend on a healthy and functional Volume Shadow Copy (VSS) environment.
If the Virtual Disk environment or VSS environment on the host are experiencing problems, this may prevent the entire Exclude List from becoming loaded into memory and objects on the Exclude List will not get excluded during the backup job.
Example Error Message in the bpbkar log at General 2 verbosity:
3:08:57.902 PM: [7004.14108] <2> ov_log::V_GlobalLogEx: Failed to create VDS Loader instance. (0x80070005)3:08:57.902 PM: [7004.14108] <4> tar_backup_tfi::UpdateExcludeListWithVHD: INF - Unable to initialize virtual disk service. .vhd files may be included for backup
Application Event Log error:
The only solution is to repair the unhealthy Virtual Disk or Volume Shadow Copy environments on the problem host. A call to Microsoft may be required.