Symptoms
- You are using Microsoft`s Storage Spaces Direct
- You are trying to preform an agentless backup of a Hyper-V VM
- The backup fails with: "| error 0x9: There is not enough space in the storage area to create a shadow copy repository file or other shadow copy data."
- Also other errors regarding VSS are to be expected.
Cause
This is an expected behavior caused by known limitation of Microsoft`s Storage Spaces Direct (S2D): Agentless backups via Hyper-V host are not supported for that type of Hyper-V storage. More Information can be found in this Microsoft Article
Workaround
To resolve the issue, do the following:
- Install Agents on guest virtual machines
- Perform backups via agents only.