How to collect VSS trace

This article explains how to collect additional VSS diagnostic data with the VSSTrace tool that is a component of the Microsoft Windows Software Development Kit (SDK).

Veeam products use Microsoft Volume Shadow Copy Service (VSS) for a variety of tasks. Sometimes it is necessary to go through the underlying VSS processes to check what method experiences issues.

VSSTrace can be used to trace VSS applications and get a detailed output that contains possible VSS error codes and events on Windows 7 and later. For details, see this Microsoft article.

Here are the steps on tow to collect diagnostic data:

1. Download the VSSTrace tool.
2. Save the file on the Veeam Agent machine. For example, C:\Users\Username\Downloads.
3. Run Command Prompt as Administrator.
4. Change directory to the folder with the VSSTrace tool. For example, cd C:\Users\Username\Downloads
5. Launch the VSSTrace tool with the following command:

   vsstrace +f 0xffff -l 255 -o vsstrace.log
   

   Mind that Log Level must be 255. For details about additional log levels, see this Microsoft Enterprise Platforms Support article.
6. Start the backup job
7. Once the backup job fails, press [Ctrl + C] to stop logs collection. The output file can be found in the folder where VSSTrace is saved (Step 2).