Disk group is reported as Unhealthy in the vSAN cluster.

Products

• VMware vSAN

Issue/Introduction

Symptoms:

• vCenter Server UI displays the following error under Cluster > Configure > Disk Management:

  Disk group status: Unhealthy

 

Environment

• VMware vSAN 7.x
• VMware vSAN 8.x

Cause

• The cache disks on the ESXi host were missing, resulting in the associated vSAN disk groups being marked as unhealthy.
• Validate the disk group configuration on the affected ESXi host and confirm that the cache disk status is marked as Absent in the vSAN UI.

• To further validate, review the /var/log/boot.gz file on the ESXi host. Hardware-level asynchronous NVMe command timeout errors will be observed, indicating a potential issue with the physical NVMe device or its controller.

2025-06-09T13:50:45.335Z cpu0:2098077)__nvme_SubmitSyncRequest: adapter:0 qid:0 req:0 error:bad0021 waiting on admin sync command  
2025-06-09T13:50:46.843Z cpu0:2098077)nvme_AttachDevice  
2025-06-09T13:50:46.843Z cpu0:2098077)nvme_PciInit: adapter->bar: 0x4521cc100000  
2025-06-09T13:50:46.844Z cpu0:2098077)CpuSched: 840: user latency of 2098693 intel-nvme-ctrl-0-cqw-69 0 changed by 2098077 vmkdevmgr -6  
2025-06-09T13:50:59.846Z cpu0:2098077)__nvme_SubmitSyncRequest: adapter:0 qid:0 req:0 error:bad0021 waiting on admin sync command  
2025-06-09T13:51:02.894Z cpu2:2098077)vmd_PciBusAddDevices: NVMe device added = 0  
2025-06-09T13:51:02.894Z cpu2:2098077)vmd_EnumerateDevices: NVMe devices attached to VMD = 0

Resolution

It is recommended to engage the hardware vendor to validate the issue and investigate any potential faults with the NVMe device or its controller.

Workaround:

As a temporary measure, power-cycling the ESXi host via the hardware management interface (e.g., iLO, iDRAC, etc.) and verify whether the cache drive is detected and the disk group is restored to a healthy state.