IT Systems Engineering

Presenting LUNs to Hyper-V 2012

Here are my notes on presenting a LUN from a 3PAR 7400 SAN to a Hyper-V 2012 server running no GUI. The SAN is connected to the server via Fiber. There is a FC switch in between which has been properly configure, zoned, etc. Multiple paths to the same LUNs are configured for redundancy and speed so we need MPIO.


1. Install MPIO feature and reboot the Hyper-V server

Note that I did not run the mpiocpl GUI or the mpclaim command as I described here earlier. You may have to do that.

2. From  inside the SAN management console, present a LUN to the Hyper-V server.

Note: while creating the volume/LUN make sure to check the size against the “Chunklet Calc” worksheet inside this spreadsheet – “3PAR Design Spreadsheet v2” so that  no chunklets are stranded. For example, it is better to have a 504 GB LUN than a 500 GB LUN. A 10 GB LUN wastes 6 GB space! A 16 GB LUN wastes nothing. So you  have to play around with the numbers in the spreadsheet.

3. At this point you have two options – use GUI disk management tool from a remote client machine running Windows 8 OR on Hyper-V server itself run these commands:


DISKPART>list disk (You may see your disk listed but if not run a rescan command)


DISKPART>list disk (Now you should see your new disk listed but it probably is offline)

DISKPART>list volume (this shows all your current volumes and their drive letters)

DISKPART>Select disk 1

DISKPART>online disk

DISKPART>detail disk (this will give you detailed info)

DISKPART>attributes disk clear readonly


DISKPART>convert mbr

DISKPART>create partition primary

DISKPART>select part 1

DISKPART>format fs=ntfs label=SANtest quick

DISKPART>assign letter E

DISKPART>list volume (you should see the new volume  now)


Full diskpart syntax can be seen here

Credits and more information here


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