vSAN Host may not enter Maintenance Mode due to Reduced availability with no rebuild state on one or more objects.

Products

• VMware vSAN

Issue/Introduction

A host may not enter Maintenance Mode (full data migration) as there are one or more vSAN objects showing "Reduced availability with no rebuild" state

Environment

VMware vSAN

Cause

Due to a previous outage an object may not have rebuild all replicas fully.

This can be observed in "Virtual Objects" section within Skyline Health

or using the "esxcli vsan debug object health summary get" command on CLI to host in the cluster, for example:

Health Status                                              Number Of Objects
---------------------------------------------------------  -----------------
remoteAccessible                                                           0
inaccessible                                                               0
reduced-availability-with-no-rebuild                                       2
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                                                                  332

Resolution

To force an object in such state to recover user can change the policy to FTT0 (Failures to Tolerate = 0) and back to original/desired Storage Policy again.

1. Ensure relevant backups are in place.
2. Identify the object stuck in "reduced-availability-with-no-rebuild" and take note of the corresponding UUID in the vSAN health message
3. SHH to any host in the cluster and force the object to FTT0 using :  

   /usr/lib/vmware/osfs/bin/objtool setPolicy -u < UUID > -p "((\"hostFailuresToTolerate\" i0))"

     4. Return the object to FTT1 (or previous policy) by applying original/desired Storage Policy using the GUI