Upgrade pre-check failed with vSAN health error, General vSAN error. Disk(s) <diskid> are unmounted, but are part of a mounted disk group.

Products

• VMware vSAN

Issue/Introduction

VSAN disk group shows unhealthy. Examining disk status using 'esxcli vsan storage list' shows disks "In CMMDS: false". 

Environment

ESXi 8.x

Resolution

Remove and re-create the VSAN disk group in question. (Only do this if the disks are showing up as 'false' for "in CMMDS")

 

1. Place the ESXi host in question into maintenance mode, with ensure accessibility: 

esxcli system maintenanceMode set --enable true -m ensureObjectAccessibility

2. Check VSAN health in the cluster prior to moving forward. If everything is green, then proceed but if there is anything that is not green, stop and engage a VSAN expert for review. Not doing so can potentially result in data loss. 

3. List out the VSAN storage: 

esxcli vsan storage list

4. Remove the disk group:

esxcli vsan storage remove -u <VSAN Disk Group UUID>

5. Recreate the disk group: 

esxcli vsan storage add -s naa.xxxxxx -d naa.xxxxxxx -d naa.xxxxxxxxxx -d naa.xxxxxxxxxxxx

(Where naa.xxxxxx is the NAA ID of the disk device, and the disk devices are identified as per these options:

    -s indicates an SSD.
    -d indicates a capacity disk.)

6. Run the esxcli vsan storage list command to see the new disk group and verify that all disks are reporting True in the "in CMMDS:" field output.

Reference : Managing and Configuring a vSAN disk group using esxcli commands