Move LUN from physical Windows box to an ESX VM without formatting

[coafark]

Hello. I'm going to be converting some physical machines (with the stand alone converter) into VMs on my ESX servers.

These servers have local drives (for OS, quorum, and other data drives) as well as multiple LUNs.

First question:

My thoughts were to convert only the local drives (skipping the LUNs since they are already on the SAN). Then have the SAN people path (allow me to see) them to my ESX servers. BIG draw back is that when I first hook up a LUN, it wants to format it. How do I hook up to it and have it known to ESX as DataStore without formatting? On the [Disk/LUN - Formatting] page, there is no way to NOT format.

Second question:

When you allow an ESX box to see a LUN that a Windows box is using, there is such contention that ESX wouldn't even let me see it. It just times out. Is there anyway around this or do I have to have the SAN people remove the paths to my Windows boxes first then add to my ESX boxes afterwards?  The SAN is controlled by another agency and this would add a lot of time in the middle and these servers are critical and can't be down for long.

If anyone can supply somewhat detailed steps I would really appreciate it.

INFORMATION:

vCenter

4.1.0, 345043

ESX Servers

4.1.0 <various patch levels>

physical boxes

Windows 2003

SAN

Hitachi Fibre Channel

[weinstein5]

First Question - You can present those LUNs to your ESX hosts and have them accessed by the VMs the use of a Raw Device Mapping (RDM) - this will allow the VM to access the LUN natively

Second Question - Yes - first do the P2V and before you start up the VM - shut down the windows box have the SAN Admin remove LUNs from the Windows server- present the LUNs to the ESX host and define the RDM for the VM

[mcowger · Accepted solution]

1) You can either use these LUNs as RDMs (raw device mappings), in which case you do NOT have to reformat them.  You simply create an RDM mapping.  See page 140 of this document: http://www.vmware.com/pdf/vsphere4/r41/vsp_41_esx_server_config.pdf

2) Windows will apply locks to the volume.  You need to fully deprovision the volumes from the old hosts before provisioning to the new ESX hosts.

[coafark]

Thanks a lot guys.  I'll try this out when the project comes closer.  I'll try and reply and let everyone know how it worked out and if other steps were needed.

I tossed around "helpfull" and "correct answer" to you guys.  mcowger got the correct for his URL link 🙂

As always super fast replies here.

UPDATE:::

I just read that doc and had a question.

NOTE To use vMotion for virtual machines with enabled NPIV, make sure that the RDM files of the virtual

machines are located on the same datastore. You cannot perform Storage vMotion or vMotion between

datastores when NPIV is enabled.

Does this part mean that you have to have the RDMs on the same DataStore as the VM (I would do this anyway).   It kind of sounds like they are telling you this two different ways.  I just want to make sure. that I'll be able to vMotion from one site to another site. (I have two stretched SANs).

I've written to the SAN people asking if NPIV is entabled.

[mcowger]

Theres absolutely no real value in using NPIV, so I wouldn't worry about it.  Just use regular (non RDM NPIV) and you wont have any problems.  Either way, this limit in the doc only relates to doing Storage vMotion, not regular ones.