Why does vSphere think I moved or copied my VM, when I have not?
I'm running ESXi on a server and managing it with vSphere client, both v5.0.0 ...everything has been fine for a while, then suddenly today when I booted from a powered-off state and tried to start my VMs, vSphere stopped 95% of the way through starting each VM and asked the question:
This virtual machine might have been moved or copied. In
order to configure certain management and networking
features, VMware ESX needs to know if this virtual machine
was moved or copied. If you don't know, answer "I copied
[truncation sic]
and then I have the options Cancel, I moved it, and I copied it ...however, I never did any such thing! (never moved or copied it, that is - I have always left all files on the datastore exactly where they were originall created - and again, I have been using this thing for a while without any problem, and this has come up suddenly.)
So I selected I copied it because I didn't know what to choose, and that sounded like the default. That let the VMs boot, and everything was fine for then - I could start and stop VMs at will, and it didn't ask me again. But then I power cycled the server, and all the VMs asked me the question again, first time I tried to start them.
Since I haven't actually moved or copied anything, what is causing this?
Answer
When you make a copy of an existing VM and keep both within the same network, you run into problems with identical/duplicate MAC addresses. So ESXi tries to detect that and asks you what you did. If you made a copy then a new MAC has to be generated to avoid conflicts. If you moved it then everything is fine and no changes are made.
The detection seems to be based on the host system's hardware and/or BIOS. Maybe your server's CMOS battery is dead or you've made some problematic changes to the BIOS recently?
The values used for the detection are stored in your VM's *.vmx file (uuid.bios and uuid.location). So every reboot ESXi calculates those values and compares them to what is stored in the file.
If worst comes to worst and you can't find the root cause then you can always circumvent the problem by defining uuid.action = "keep" in your *.vmx file. This will always choose "I moved it". You just have to be extra careful when you really do make a copy of the VM.
http://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=1541