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tfpjr
Contributor
Contributor

esxi 5 storage vmotion with rdm's

current environment is esxi 5 across all hosts and running vcenter 5.

about to begin the process of getting all datastore luns to vmfs 5.54.

we've read that if you storage vmotion guest that have rdms assigned to them, the rdm is copied to a .vmdk file during that process.

any truth to this?  it makes no sense why this would occur.

thanks,

tim

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rickardnobel
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Champion

It is possible to convert a virtual mode RDM to a vmdk, but make sure to select Advanced when doing Storage vMotion to select which guest disks you want to move.

My VMware blog: www.rickardnobel.se
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tfpjr
Contributor
Contributor

but we do *NOT* want to convert any rdm's to vmdks during the storage vmotion.

by default, will a storage vmotion convert them?

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rickardnobel
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My understanding is that if doing a cold storage migration (VM power off) the RDM will be converted to a VDMK file at the new destination, but not when doing "hot" Storage vMotion.

See this KB for details: http://kb.vmware.com/kb/1005241

My VMware blog: www.rickardnobel.se
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vGuy
Expert
Expert

Hello Richard, Tim,

It seems the RDM is only converted when it's format is changed(thin/thick). Else only the mapping file is moved from the source to the destination datastore:

http://blogs.vmware.com/vsphere/2012/02/migrating-rdms-and-a-question-for-rdm-users.html

hth..