vSAN Objects in 'reduced-availability-with-no-rebuild' after taking a host into maintenance mode

Products

• VMware vSAN

Issue/Introduction

• After taking a vSAN host into maintenance mode, some of the objects may change its state to 'reduced-availability-with-no-rebuild'.
  
  
• vSAN Skyline health in vCenter shows the warning for the object stuck in  'reduced-availability-with-no-rebuild'. 
  
  
  
  

• vSAN object health can be validated from ESXi CLI of any host in the cluster using the below command.

  # localcli vsan debug object health summary get
  
  

•  

  In vCenter UI, Cluster > Monitor > vSAN > Resyncing Objects will show under Scheduled resyncing. However, the resync will not be initiated even after clicking on 'Repair object immediately' option.

Environment

VMware vSAN 7.x
VMware vSAN 8.x

Cause

Object was unable to rebuild since the ownership of the affected was still with the host in maintenance mode.

Below command output from the vSAN host shows the ownership of the all the object stuck in reduced-availability-with-no-rebuild are with the host in maintenance mode.

# esxcli vsan debug object list --health=reduced-availability-with-no-rebuild



Sample Output:

Object UUID: ########-####-####-####-############
   Version: 20
   Health: reduced-availability-with-no-rebuild
   Owner: Host-01       <<--- Host taken into maintenance mode
   Size: 30.00 GB
   Used: 11.68 GB
   Used 4K Blocks: 11.68 GB
   Policy: 
      stripeWidth: 1
      hostFailuresToTolerate: 1
      spbmProfileId: ########-####-####-####-############
      spbmProfileGenerationNumber: 3
      objectVersion: 20
      replicaPreference: Performance
      CSN: 12977
      SCSN: 12988
      spbmProfileName: vSAN Default Storage Policy

   Configuration: 
      RAID_1
         Component: ########-####-####-####-############
           Component State: ABSENT,  CSN: STALE (12967!=12977), Address Space(B): 32212254720 (30.00GB),  Disk UUID: ########-####-####-####-############,  Disk Name: naa.################
           Votes: 1,  Capacity Used(B): 6266290176 (5.84GB),  Physical Capacity Used(B): 6203375616 (5.78GB),  Host Name: Host-01       <<--- Host taken into maintenance mode
         Component: ########-####-####-####-############
           Component State: ABSENT,  Address Space(B): 32212254720 (30.00GB),  Disk UUID: ########-####-####-####-############,  Disk Name: naa.################
           Votes: 1,  Capacity Used(B): 6266290176 (5.84GB),  Physical Capacity Used(B): 6203375616 (5.78GB),  Host Name: Host-02
      Witness: ########-####-####-####-############
        Component State: ACTIVE,  Address Space(B): 0 (0.00GB),  Disk UUID: ########-####-####-####-############,  Disk Name: naa.################
        Votes: 1,  Capacity Used(B): 12582912 (0.01GB),  Physical Capacity Used(B): 4194304 (0.00GB),  Host Name: Host-03

   Type: vdisk
   Path: /vmfs/volumes/vsan:################-################/########-####-####-####-############/VM_name.vmdk (Exists)
   Group UUID: ########-####-####-####-############
   Directory Name: None

Resolution

Perform OwnerAbdicate for the affected objects.

Below command was used to perform the OwnerAbdicate the objects.
# vsish -e set /vmkModules/vsan/dom/ownerAbdicate <Affected_Object_UUID>

OnwerAbdicate will force the object to refresh the ownership to another host in the vSAN Cluster, and it will help to rebuild the object.

Additional Information

Object health issue 'Reduced availability with no rebuild'