Article number
000004064
Affected Versions
All
Source Hypervisor
All
Target Hypervisor
All

Problem with Importing VPGs After Upgrading ZVM To More Than One Version Higher

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Summary

An administrator may need to perform an upgrade that is a multi-step upgrade (i.e. 6.5 -> 7.5) which is only possible via an uninstall/re-install on desired code version. The administrator would typically Export VPGs via the Diagnostic Utility and try to Import VPGs using the generated XML after the new installation on desired code version is up and running. However, the Import VPGs functionality appears to fail.

Root Cause

This is a known product limitation as the ExportedSettings.xml has gone through changes over the course of many code versions, thus, some fields may exist that no longer exist or vice versa.

Symptoms

When providing the ExportedSettings.xml file to the Diagnostic Utility -> Import VPGs wizard post-multi step upgrade, the operation fails and no VPGs are created.

The Diagnostic Utility should also present the following error when attempting to Import VPGs from an ExportedSettings.xml from more than one code version older:

Zerto exception: System.NullReferenceException, mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089

Solution

There are two workarounds, one from a reactionary standpoint and the other from a proactive standpoint:

  1. Prior to removal of the VPGs/uninstallation of Zerto, from the "VPG" screen in the Zerto GUI, press the Export button to generate a CSV file containing all VPGs details.

  2. Once Zerto is re-installed on the desired code version, simply open the CSV file to track down where each recovery disk is located so Manual Preseeding can be done.

  3. Follow the steps in the How to Preseed Volumes KB article to set up the manual preseed disks.

  4. If #1 was not done prior to removal of the VPGs, then the only option to utilize the preseed disks is to find each disk manually, then follow the steps in the aforementioned KB article.

  5. The only other option is to create the VPGs without selecting preseed disks, but this would result in a full, initial sync, and all new mirror volumes being created.