When vmware changes the mac address of the virtual machines

Hello,

if the virtual machine's mac address are in automatic mode, there are some situations where the virtual machine's mac address can change.

AFAIK, this situations are:

• When a virtual machine is powered on again, it might acquire a different MAC address.
• The MAC address changes on the virtual NIC during the hardware (version) upgrade.
• Every time the virtual machine is migrated (vMotion or Storage vMotion)
• When a virtual machine is cloned, the network adapter(s) are given new MAC addresses.

Additional bibliography

vSphere 5.5 Documentation Center

VMware KB: Virtual machine MAC address conflicts or have a duplicate MAC Address when creating a virtual machine

Best regards,

Pablo