Friday, November 25, 2011

Cloning nested ESXi 5 hosts results in duplicate MACs.

While building an vCenter 5 lab environment for a 1000v training class I ran into an issue with the "Management Network" vmkernel NIC's on each machine having a duplicate MAC address.

The ESXi hosts were "nested" virtual ESXi hosts created from a template captured after installing ESXi from the iso without letting the installation reboot, which seems to be the recommendation for deploying nexted ESXi for a lab.

In order to resolve the issue I simply selected "Restore Network Options" on each host and then reentered the VLAN and IP information. Not too bad, just a little tiresome to repeat.

You can also do the same from the ESXi Shell available in the troubleshooting options if you wish. Once you enable ESXi Shell from the troubleshooting you can access the shell directly from the console with the Alt+F1 key combination.

The instructions to tackle this problem from the shell are here: