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Dell PE 2950, PERC 6/i Controller. - ESXi 5.1 installed/Boot from USB drive - 2 x 1 TB SAS drives in RAID 1 - Datastore1 - 1x 2TB SATA drive set as RAID 0

We wish to host all our VMs from Datastore1 and add the 2 TB SATA as a Raw Disk mapping to one of the VMs. This option is at the moment greyed out. We wish to use this as a simple storage no other purpose.

My questions 1. Does PERC 6/i support RDM, if not is there a work around to add the local SATA as a RDM. 2. I was only able to see our 2 TB drive in Vsphere after configuring it as RAID0, our intention is to make this as a NON RAID drive. Does removing it from the RAID help in anyway?

P.S - I understand one workaround is to create a VM on top of this 2 TB. I am worried about several other factors and wish to keep this as a last option.

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VMWare only support SAN LUNs as RDMs over FC/FCoE and iSCSI, there's no official way of doing this with local disks. HOWEVER if you google about a bit you'll find a few hacks that seem to work for some people, though there's no certainty that your kit will work until you try it, and even then you'll be in an unsupported situation.

Serverfault is a site for professional sysadmins who pride ourselves on uptime and supportability so you'll rarely find these hacks detailed on this site as they inherently remove support. Hope you understand.

Oh and one final note, you're not really using RAID 0 are you? There's no excuse for it.

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Its good that you asked, I have always wanted to ask this question on serverfault. We don't want this 2 TB drive to be in a RAID at all, we want it to be NON-RAID. What will happen if we simply not configure this drive in the RAID? will we still be able to see it in ESXi? – user167643 Apr 25 '13 at 9:52
I don't think so. In that case you would use raid 0 with just a single drive. People generally advise against raid 0 because if any drive in the set goes you lose the whole lot. In a lot of cases you are much better off using the disk in a raid set (>0) because as well as redundancy performance is better than with a single disk. – JamesRyan Apr 25 '13 at 10:35
@user167643, sorry for the delay (went to see 'Iron Man 3' :) ), anyway it's irrelevant what you do with it RAID-wide, if it's locally attached (i.e. SATA) you can use it as a VMFS-formatted datastore but just not as an RDM (why did you want that anyway?). – Chopper3 Apr 25 '13 at 16:25
Wow I am planning for it this weekend, hopefully..:). – user167643 Apr 26 '13 at 8:41
And thanks for your inputs. I am now considering a NAS due to this limitation. – user167643 Apr 26 '13 at 8:42

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