After performing a bulk migration of virtual machines (VMs) from an on-premises environment to VMware Cloud (VMC) on AWS, some users have encountered an issue where cloning these migrated VMs results in duplicated MAC addresses. This duplication can lead to network conflicts, causing connectivity problems within the virtual environment.
VMware HCX
The duplication of MAC addresses occurs due to specific settings applied during the bulk migration process. Here's a detailed breakdown of the factors contributing to this issue:
On-Premises VM Configuration
Bulk Migration Settings via vSphere Client (HCX Plug-in)
Post-Migration VM Configuration on VMC
To prevent MAC address duplication when cloning VMs post-migration, follow the appropriate steps based on whether the VMs are already migrated to VMC or still reside on-premises.
Change MAC Address Setting from Manual to Automatic
Disable the "Retain MAC" Option During Bulk Migration