Datastore fails to mount and reports "Invalid metadata" error in vmkernel logs

Products

• VMware vSphere ESXi

Issue/Introduction

Symptoms:

• Mounting the datastore fails with error:

Mount VMFS volume failed!

An error occurred during host configuration. Operation failed, diagnostics report: Unable to find volume uuid [########-########-####-############ Ivm [snap-########-########-####-############] devices

• Running  'df -h' and 'esxcli storage' commands on ESXi hosts get stuck or throws error:

# df -h
VmFileSystem: Slow refresh failed: Cannot open volume: /vmfs/volumes/########-########-####-############
Error when running esxcli, return status was: 1
Errors:
Error getting data for filesystem on '/vmfs/volumes/########-########-####-############': Cannot open volume: /vmfs/volumes/########-########-####-############, skipping.

Environment

vSphere ESXi 8.0

Cause

• Metadata corruption reported on affected datastore.

vmkernel.log of an ESXi reports:

2025-08-28T04:42:38.347Z cpu8 :2167420) WARNING: FS3: 608: VMFS volume '##########################/########-########-####-############ on naa.###########################:1 has been detected corrupted

2025-08-28T04:42:38.347Z cpu8:2167420) WARNING: Res3: 7472: '##########################': [rt 1] Cluster harvesting resulted in an unrecoverable error: Invalid metadata

2025-08-28T04:42:38.347Z cpu8:2167420) WARNING: FS3J: 1765: Failed to reserve space for journal on ########-########-####-############ : Invalid metadata

Resolution

1. Vacate affected datastore by performing storage vmotion of VMs running on it to a good known datastore.
   
   
2. Unmount affected datastore from all hosts and run VOMA check on it to analyze corruption:
   
   Ref : Using vSphere On-disk Metadata Analyzer (VOMA) to check VMFS metadata consistency.
   
   
3. Depending on results of VOMA check, decision could be made if the datastore is good to use or needs to be recreated.