vSAN Object Health Errors in Skyline Health Reports

Products

VMware vSAN

Issue/Introduction

Symptoms:

Skyline health reports errors for vSAN object health and stats DB object.
vSAN health check is reporting 'Reduced availability with no rebuild' for Stats DB

Verify the object status using the command : "esxcli vsan debug object health summary get"

esxcli vsan debug object health summary get
Health Status                                              Number Of Objects
---------------------------------------------------------  -----------------
remoteAccessible                                                           0
inaccessible                                                               0
reduced-availability-with-no-rebuild                                     479
reduced-availability-with-no-rebuild-delay-timer                           0
reducedavailabilitywithpolicypending                                       0
reducedavailabilitywithpolicypendingfailed                                 0
reduced-availability-with-active-rebuild                                   0
reducedavailabilitywithpausedrebuild                                       0
data-move                                                                  0
nonavailability-related-reconfig                                           0
nonavailabilityrelatedincompliancewithpolicypending                        0
nonavailabilityrelatedincompliancewithpolicypendingfailed                  0
nonavailability-related-incompliance                                       0
nonavailabilityrelatedincompliancewithpausedrebuild                        0
healthy                                                                    0

Verify the objects raid configuration using the command : "esxcli vsan debug object list".

Example :

esxcli vsan debug object list

Object UUID: ########-####-####-####-############
   Version: 19
   Health: reduced-availability-with-no-rebuild
   Owner: esx############.####.###.###
   Size: 255.00 GB
   Used: 2.73 GB
   Used 4K Blocks: 1.76 GB
   Policy:
      stripeWidth: 1
      cacheReservation: 0
      proportionalCapacity: [0, 100]
      hostFailuresToTolerate: 1
      forceProvisioning: 0
      spbmProfileId: ########-####-####-####-############
      spbmProfileGenerationNumber: 0
      replicaPreference: Performance  >>>>>>> ( Performance refers to Raid 1)
           iopsLimit: 0
      checksumDisabled: 0
      CSN: 30893
      SCSN: 30833
      spbmProfileName: VM Storage Policy -RAID1 FTT1

   Configuration:

      RAID_1
         Component: ########-####-####-####-############
           Component State: ACTIVE,  Address Space(B): 273804165120 (255.00GB),  Disk UUID: ########-####-####-####-############,  Disk Name: naa.################:2
           Votes: 2,  Capacity Used(B): 1476395008 (1.38GB),  Physical Capacity Used(B): 1459617792 (1.36GB),  Total 4K Blocks Used(B): 942419968 (0.88GB),  Host Name: ###############.####
         Component: ########-####-####-####-############
           Component State: ACTIVE,  Address Space(B): 273804165120 (255.00GB),  Disk UUID: ########-####-####-####-############,  Disk Name: naa.################:2
           Votes: 1,  Capacity Used(B): 1484783616 (1.38GB),  Physical Capacity Used(B): 1468006400 (1.37GB),  Total 4K Blocks Used(B): 949825536 (0.88GB),  Host Name: ###############.####

   Type: vmnamespace
   Path: /vmfs/volumes/vsan:################-###############/ABCDEF(Exists)
   Group UUID: ########-####-####-####-############
   Directory Name: ABCDEF

Environment

VMware vSAN 6.x
VMware vSAN 7.x
VMware vSAN 8.x
vSAN OSA

Cause

All objects, including the vSAN stats DB object, are in a "reduced availability with no rebuild" state due to the unavailability of the required number of hosts or fault domains.
The assigned storage policy requires more fault domains or hosts than are present in the cluster, preventing objects from achieving full compliance

Navigate to vSAN cluster > Configure > Fault domain.

From the above screenshot it is confirmed that vSAN cluster is configured with 2 fault domains.
For a RAID-1 configuration with Failures to Tolerate (FTT) set to 1, a minimum of 3 fault domains are required. This is because data is mirrored across two fault domains, and a third is necessary to maintain quorum.
As the current fault domain configuration is insufficient (only 2 fault domains present), the addition of one fault domain or removal of the existing fault domains is necessary for proper functionality.

Resolution

To resolve the issue, please proceed with one of the following options:

Configure minimum required number of fault domains.
Remove the fault domain altogether.
Apply a storage policy to impacted objects that would be compatible with the number of hosts / fault domains

Important Note: Before proceeding with any of the above actions, ensure you have proper backups of all VMs.

Additional Information

What are vSAN Policies