Article number
Affected Versions
Source Hypervisor
Target Hypervisor

How to troubleshoot when VM(s) do not boot on Failover or Move

Viewed 480 times


General VPG consistency issue or as a result of not force syncing after upgrading from one of the affected builds (ZVM version 6.5U0, 6.5U1, or 6.5U2)

Page 4 of 6.5 u4 p1 Release Notes – Zerto Virtual Replication states:

"Zerto has identified a data consistency issue introduced in the ZVM 6.5 version. While the issue is only triggered under very unique circumstances of a nested Bitmap Sync, we are taking aggressive action to resolve this issue for our user community. Zerto has fixed this issue in 6.5U3, and strongly recommends that all customers currently running versions 6.5U0, 6.5U1 or 6.5U2, upgrade to ZVR 6.5U3 or above.

To ensure data consistency, upon upgrade, and after upgrade of the VRAs, ZVM will automatically force sync all VPGs replicating out of a VMWare/Hyper-V source site that was on ZVM version 6.5U0, 6.5U1, or 6.5U2.

Customers upgrading from version 6.0 or older are unaffected by this issue.

To manually control the timing, order, and pace of the VPG force sync, you can override the automatic force sync; during the Upgrade process, select the checkbox to override the automatic force sync. If you choose this option, you are obligated to manually force sync all VPGs that were replicating out of an earlier 6.5 VMWare/Hyper-V source site, after all your VRAs are upgraded to version 6.5U3.

It is important to note that if a MOVE, FAILOVER LIVE, or CLONE operation was used with ZVM 6.5U0, 6.5U1, or 6.5U2 on a production VM, you are encouraged to check the consistency of this VM. For assistance, please contact Zerto Support.

Note: Forced-sync is not required if you are upgrading from 6.5U3 to later versions." VM(s) in a VPG do not boot correctly during Failover or Move.


Try Force Syncing the VPG, running the Failover or Move process again, and see if that allows VM to boot correctly.

A second troubleshooting step would be to try and Clone the VM outside of Zerto per this article:

If all troubleshooting steps in this article are followed but the issue persists, kindly contact Zerto Support.