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How to Expand a Protected Volume to Beyond 2TB

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By default, expanding a protected volume to a size beyond 2TB will result in the VPG entering "Needs Configuration" state and the VM will have to be re-created (results in delta-sync). An administrator may want to prevent that behavior and enable expanding disks to over 2TB without resulting in unnecessary syncs.

As ESXi 5.5.x and 6.0.x do not support hot disk expansion above 2TB. (Volume expansion of a powered on VM). Please see the NOTE below for ESXI 6.5 and above.

The VRA on the target site, which can only perform a hot-expansion, will not be able to expand the disk. Therefore, the protected and mirror volumes will not match in size. For more information on this VMware limitation see this VMware article .

NOTE: VMware limitation has been changed if the user is running ESXi 6.5 and above versions. Hardware Version 13 (vHW 13) is not required for this to work, therefore just the vSphere platform and not the VM has to be upgraded.


  1. Verify the recovery VRA that the recovery disk associated with the protected disk being expanded is on.
  2. If there are other VMs replicating to this same VRA, it is recommended to evacuate the VRA outside of the VM with the disk being expanded as the VRA needs to be powered down in a later step. If evacuation is needed, follow the below steps:
    • In the Zerto GUI, under the "Setup" tab, choose "Change VM Recovery VRA" on the relevant VM(s) to evacuate.
    • Select a different VRA and click done.
  3.  Once all VMs outside of the one with the disk to be expanded recovery volume is migrated off the recovery VRA, power down the recovery VRA.
  4. Resize the disk on the protected source VM as required. 
  5. Wait for the VPG to finish updating. 
  6. Power on the recovery VRA.
  7. (If required) Follow Step 2 once more to move the VMs back to this Recovery VRA.
NOTE: Each "Change VM Recovery Host" operation will result in a short bitmap sync.