VM Cloning with Raw Device Mapped drive

[Cyberfed27]

Hey folks...need some help.

I have a VM that lives on a 500GB Lun. The VM has a 60GB C: drive (OS) and a 1.5TB Raw Device Mapped LUN.

My problem is I am trying to clone this machine to have a backup copy of it. However when I try to clone it to a 500GB or even a 1TB datastore it says I do not have enough space to do so. I have gone in and removed the RDM 1.5TB LUN in the cloning options so that it would only clone the C: drive. Still same message.

Also I noticed that the 500GB datastore which the VM currently lives has a 1.5TB .vmdk file which I assume is the Raw Device Mapped LUN. Why is this creating a file if its a SAN mapped drive. How did it even create a 1.5TB file on a 500GB datastore?!?

[kjb007]

The RDM file that is used to reference the raw device reports itself as the same filesize as the raw device itself. The amount of space it actually takes up on your datastore is very little.

When you attempt the cloning, what is the block size of the datastore that you are trying to clone to? If your block size is not sufficiently large, you will get a space error.

vExpert

VMware Communities Moderator

vmwise.com / @vmwise

-KjB

[Cyberfed27]

Good to hear about the file size of the RDM vmdk. That had me a bit worried.

I too thought it was a block size issue after reading some other posts. So I created a fresh 1TB LUN datastore with an 8MB blocksize (2TB Max size disk).

Same result :smileysad:

[athlon_crazy]

Do you able to clone it via CLI?

$vmkfstools -i /vmfs/../source.vmdk -d thin /vmfs/…/destination.vmdk

Try start with C:\ drive first and don't forget to a snapshot or power off the VM first!

[kjb007]

Hmm. It may be complaining about the source. What block size is on the datastore you are migrating from?

vExpert

VMware Communities Moderator

vmwise.com / @vmwise

-KjB

[Cyberfed27]

1MB block size on the datatore it currently lives on.

Could that be why? Am I screwed?

[kjb007]

That certainly appears to be the reason. Instead of a clone, use vmware converter standalone and treat the vm as a physical server. That should allow you to continue. If nothing else, you can "remove" the raw device from the vm, clone it, and then add the raw device back to the original. Converter should work though.

vExpert

VMware Communities Moderator

vmwise.com / @vmwise

-KjB

[Cyberfed27]

Good idea, I like it. Its a production fileserver that cant go down. So I'm a bit gunshy to mess with it too much during the day.

I like the standalone VMware converter idea.

I smell some after hours tinkering! I will let you know the results. Thanks again!

[Cyberfed27]

I used VMware Converter Standalone to do a import of the machine with just the C: (OS) drive.

It worked flawlessly. I feel a whole heck of alot better knowing I have a clone of this production server now!

Thanks again for the help!