Tag: Retain MAC

VMware

HCX Retain MAC, Network Extension and DHCP: Keeping IP Addresses and Licences Intact at Cutover

Retain MAC keeps a migrated VM's MAC address and Network Extension keeps its IP and gateway, but DHCP reservations and licences survive only when both are planned per VM. This guide covers migration type behaviour, DHCP across extended networks, ARP, unextend and a cutover runbook.

VMware

HCX Bulk Migration Fails: "The MAC Address of the VM Belongs to the Reserved MAC Range" Explained and Fixed

HCX Bulk Migration with Retain MAC fails when a VM's MAC address is in VMware's reserved 00:50:56 or 00:0C:29 ranges. Here is how vSphere allocates MACs, why HCX refuses them, and the two fixes.