vancod
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Convert RDM to VMDK

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I have a series of VMs that have RDMs. I want to convert them to VMDKs.

This is a stand-alone ESX 3.5 host that is managed by vCenter 2.5 (both Update 4)

I have read where this can be accomplished as an "automated" process by a cold migration - but I have nothing to cold migrate to/from.

I have seen trheads that alude to particular web post on this process using VMKFSTOOLS - and the example in that web post CLEARLY shows a VMDK being turned into an RDM - the opposite of what I need. If the command line is required I'm OK with that, but woud like to see a sample of the syntax because the available man pages are typical: lots of dry data, no real-world examples of the syntax in action

Help appreciated - I have the storage vmotion plug-in installed as the end-game here is to migrade from an old EMC to a new HP EVA, but may need to change the disk compatibility mode of the RMDs as they are currently set to "physical" and it would appear they may need to be set to "virtual".

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AndreTheGiant
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If you have 2 datastore you can use SVMotion to move the VM in another datastore, this will convert the RDM to a VMDK disk.

Otherwise you can use vmkfstools from CLI to copy the RDM to a VMDK (with the VM powered-off), then remove the RDM from the VM and add the new vmdk.

Andre

Andre | http://about.me/amauro | http://vinfrastructure.it/ | @Andrea_Mauro

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vancod
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I should mention that I can do these as a "live" or "cold" migration - whatever works

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AndreTheGiant
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If you have 2 datastore you can use SVMotion to move the VM in another datastore, this will convert the RDM to a VMDK disk.

Otherwise you can use vmkfstools from CLI to copy the RDM to a VMDK (with the VM powered-off), then remove the RDM from the VM and add the new vmdk.

Andre

Andre | http://about.me/amauro | http://vinfrastructure.it/ | @Andrea_Mauro

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vancod
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Thanks AtG - any chance you'd have example syntax? I'm somewhat confused.

I will try SVMotion once I can reboot to reset the compatibility mode - in present state it does not show the RDM disks at all.

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AndreTheGiant
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To use vmkfstools for copy a vmdk:

vmkfstools -i SOURCE DEST

Andre

Andre | http://about.me/amauro | http://vinfrastructure.it/ | @Andrea_Mauro
vancod
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Ah! So it's that easy because the RDM still appears as a VMDK, even though it's just a pointer.....

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vancod
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Well, of the 5VMs/10RDMs I needed to migrate, everything went smoothly except for one migration. One of the VMs that had 3 RDM drives appeared to have sucessfully migrated all 3, but when we booted the host one of the disks was an unuexpcted size (200GB instead of 143) and showed as an unpartitioned device.

The solution for this RDM was simply to re-attach it and (again with the VM off) do a manual clone from command line on the ESX host. We simply presented this as a new drive, selecting the newly cloned VMDK as the target. This process worked as expected.

I am confused about the failure as none of the logs (on the ESX host or for the VM itself) showed that there was an error in the RDM-to-VMDK clone, but I'm glad it was just this single incident, and that recovery was simple (but time consuming).

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