Guest OS Customization may fail when cloning groups of VM's from a template if network settings are changed.

Products

• VMware vCenter Server

Issue/Introduction

Symptoms:
When customizing a VM during cloning, failure of Guest OS Customization may occur if there are changes to the network configuration such as adding additional NIC's or creating a new vSwitch during cloning.

When reviewing sysprep logs, you may see the following errors:
 

2023-03-27 14:30:26, Info                         [NETIOUGC.EXE] TCPIP: Transition to context 2 accepted for key 'Interfaces'.
2023-03-27 14:30:26, Error                        [NETIOUGC.EXE] TCPIP: Unable to transition to subkey '<MAC_ADDRESS> (under 'Interfaces'): 0x57.
2023-03-27 14:30:26, Error                        [NETIOUGC.EXE] TCPIP: Error processing subkeys under 'Interfaces' registry key: 0x57.
2023-03-27 14:30:26, Error                        [NETIOUGC.EXE] TCPIP: Error while processing the the 'Interfaces' registry key.
2023-03-27 14:30:26, Info                         [NETIOUGC.EXE] TCPIP: Returning from context 2 ('Interfaces') to context 1 ('Software\Microsoft\Windows NT\CurrentVersion\UnattendSettings\Netio').

Note that <MAC_ADDRESS> will contain the MAC for the VM in question.

Environment

VMware vCenter Server 7.0.x
VMware vCenter Server 8.0.x

Cause

This can occur due to timing of operations where MAC addresses are changed due to duplicate MAC's.  The timing results in a customization file which contains a MAC address that doesn't match the current MAC address of the VM, and customization fails.

Resolution

This issue is due to be fixed in a future release.

Workaround:
This issue has been seen when automating the cloning and customization of multiple VM's simultaneously via Ansible.  It is possible that it could be seen in other circumstances, however the workaround would be to implement a pause in the automation after all of the cloning operations succeed before powering non VM's, to allow for all MAC address updates to propagate.