Physical RDM disk

[HCC]

Hi, I have a VM that we wanted to add a 120GB fibre channel LUN to. We generated a Virtual WWN, masked and zoned the space...everything looks fine. I added the RDM to to VM and choose to keep vmdk with the VM which I believe is recommended. VM can see the drive and I was abel to initialize and format the drive fine. I looked at the Data Store where the VM sits and noticed that it looks like I see a vmdk file of 125,798,400.00 VIrtual Disk which, when I click on it, appears at the bottom of the window as 120GB.

Just wondering if this is normal? I figured the file would be much smaller as it points to an external drive or maybe I am reading this wrong ?

Thanks

[Gerrit_Lehr]

That is correct behavior. Even though the RDM is only a pointer file, the on the Datastore it is shown as the overall LUN size.

The same way .vmdk files are shown in the size of the virtual disk, when physicaly, they are only small header files and the flat.vmdk is the real disk file.

Kind regards,

Gerrit Lehr

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[HCC]

Okay..so just to clarify, even though the disk is an RDM I still need to have that sized space free in my Data Store ?....so in this case I stil need 120GB free in the Data Store in order to add the drive.

[Gerrit_Lehr · Accepted solution]

No, the size is not physically used on the datastore and it should not be shown as used when comparing the datastore full size / free space. That is only the way VIClient shows the files.

Kind regards,

Gerrit Lehr

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[HCC]

Hi, is there a way to test to ensure the VM is using the Generated WWN, virtual path I think it is called, and not just the storage assigned to ESX ?

Also, how do I implement security with a generated WWN if the ESX hosts also need permission to see the space? In theory, if ESX can see the space can't I assign it to any VM as a RDM? I used NPIV in BladeCenter in a non-Vmware related project however the SAN switch could actually see the WWN broadcasted unlike ESX where I have to manually enter it ?

Thanks for the assistance.