Hyper-V backup fails with error 'Operation timedout of gathering writer metadata'
Problem description
Hyper-V VM backup fails with 'Hyperv backup failed: Vss Error: Operation timedout of gathering writer metadata hr = -2147212520'.
Cause
This issue can occur if the Volume Shadow Copy Service (VSS) writers did not respond to a query from the VSS service (OS level operation).
Traceback
- Follow the instructions provided in the Logs article to retrieve job logs.
- Extract the logs and go to Phoenix<YYYYMMDD>_<timestamp>.log file to see the below traceback in the logs:
[2021-08-05 20:00:59,266] [ERROR] <_MainThread(MainThread)> HypervAgent: Hyperv backup failed: Vss Error: Operation timedout of gathering writer metadata hr = -2147212520
[2021-08-05 20:00:59,267] [ERROR] <_MainThread(MainThread)> Error <class 'pyvss.VssException'>:Vss Error: Operation timedout of gathering writer metadata hr = -2147212520. Traceback -Traceback (most recent call last):
File "agentPartnerProcess.pyc", line 85, in _process_request_start
File "agents\hyperv\hypervAgent.pyc", line 68, in process_backup_start
File "agents\hyperv\hypervBackup.pyc", line 341, in prepare
File "agents\hyperv\vssHelper.pyc", line 127, in discover_vm
File "agents\hyperv\hypervVssUtils.pyc", line 155, in gather_writer_metadata
VssException: Vss Error: Operation timedout of gathering writer metadata hr = -2147212520
Event viewer:
Log Name: Application
Source: VSS
Event ID: 12347
Task Category: None
Level: Error
Keywords: Classic
User: N/A
Computer: abcd.Example.net
Description:
Volume Shadow Copy Service error: An internal inconsistency was detected in trying to contact shadow copy service writers. The Registry Writer failed to respond to a query from VSS. Check to see that the Event Service and Volume Shadow Copy Service are operating properly, and please check the Application event log for any other events.
Operation:
Gathering Writer Data
Executing Asynchronous Operation
Resolution
Scenario 1
- Run the command vssadmin list writers and make sure all VSS writers are stable.
- Follow the instructions in the Microsoft article Event ID 12347 — Volume Shadow Copy Service Operations.
- Rebooting the Hyper-V host may resolve the issue.
Scenario 2
- The command vssadmin list writers doesn’t report any output.
- Follow the instructions in the Microsoft article No VSS writers are listed when you run the vssadmin list writers command in Windows Server.
- Rebooting the Hyper-V host may resolve the issue.