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Affected Versions
Source Hypervisor
Target Hypervisor

After Migrating To A New Resource Pool, Operations Such As Failover Test And Rollback Will Fail For “Object Reference Not Set To An Instance Of An Object”

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An administrator may come across a failure on a Failover Test or Rollback operation after making changes to the related orgVDC's Resource Pool.

Root Cause

The Old Resource Pool MoRef was found to still be present in the VCD Database. This lead to Zerto still seeing the Old Resource Pool and trying to use it, which of course is outside of the orgVDC available resources.


After performing the below, DR Operations, such as a Failover Test and accompanying Rollback, will fail for Object reference not set to an instance of an object:

  1. New Resource Pool added to orgVDC in Cloud Site where the orgVDC is already in the associated ZORG on the ZCM.

  2. Change VM Recovery Host operations are successful to move all related VM replication to new hosts/storage that is part of the new Resource Group.

  3. Old Resource Pool is removed from the orgVDC. This, in turn, means the Old Resource Pool is no longer part of the ZORG in the ZCM.

  4. Old Resource Pool is completed destroyed from VCD/VC, therefore the MoRef should no longer exist.

Note: The recovery VMs will spin up in the root context of the cluster and appear to be utilizing the Old Resource Pool resources.

Review into the logs as well as the ZVM and ZCM DBs will show the Old Resource Pool MoRef will no longer be present. However, the VCD Reflection file will still show the Resource Pool as attached to the orgVDC even though the orgVDC in VCD's GUI only shows the New Resource Pool configured.


To resolve this issue, the administrator should engage VMware Support to assist in removal of any/all stale entries regarding the old Resource Pool MoRef.

Once this is done, further DR Operations, such as a Failover Test, should succeed and use the New Resource Pool.