Datto Windows Agent: Excluding the Shadow Copy Optimization Writer for VSS backups
Topic
This article describes the procedure to exclude the Shadow Copy Optimization VSS writer from being used in Datto Windows Agent backups due to filesystem consistency issues in some scenarios.
Environment
- Datto Windows Agent
- Microsoft Windows 2016
- Microsoft Windows 2019
Description
The procedure outlined below should only be necessary on systems reporting the post backup file system integrity check failed due to cluster accounting mismatches, and presenting VSS event IDs 8219 or 8220.
The Shadow Copy Optimization writer is, as the name implies, an optimization and not strictly necessary nor critical to backup health. The writer’s job is to delete certain temporary files or files that do not contain user or system state.
In some instances, this writer can timeout performing its operations. When such a timeout occurs, an event is logged to Windows application log with the source VSS and ID either 8219 or 8220, with the text “Ran out of time while expanding file specification” or “Ran out of time while deleting files.”
NOTE These are informational messages and not warnings or errors.
The resulting backup may then report cluster accounting mismatches when the datto file system integrity check is run. It is safe to exclude the Shadow Copy Optimization writer from backups in these instances
Procedure
To exclude the Shadow Copy Optimization VSS writer from future backups, follow the steps below.
- Open the GUI for the Datto appliance.
- Click the Protect tab.
- Find the agent you wish to configure and click Configure Agent Settings.
- Scroll down to the Advanced section to the VSS writer exclusion settings.
- Disable the Shadow Copy Optimization VSS writer.
- If backup performance issues persist after making these changes, contact Datto Technical Support.
