topic Re: Moving RDM LUNs to new storage with SnapMirror in VMware Solutions Discussions

Moving RDM LUNs to new storage with SnapMirror

klemen_bregar — Wed, 04 Jun 2025 10:46:54 GMT

Hello!

We have a VM (vmware) with 2 RDM LUN's placed on old storage (CDOT)).

I have to move those RDM LUNs to new storage (also CDOT) with snapmirror.

Is this procedure OK?

1. shutdown VM

2. remove RDM disks on VM

3. dettach RDM LUN's on vmware

4. LUN unmap on old storage

5. snapmirror update

6. snapmirror break

7. LUN map back to vmware on new storage (do i have to use the same LUN ID?)

8. add RDM disks to VM

9. VM power on

Is this procedure OK or there is any other way? What about LUN ID's?

Thank you!

With regards,

Klemen

Re: Moving RDM LUNs to new storage with SnapMirror

cedric_renauld — Tue, 03 Nov 2020 16:37:10 GMT

Hello,

I m not sure, but just to check you need to validate the LUN serial Number

It's MUST be the same on SRV and DST NEtApp

lun show -vserver vs1 -path /vol/vol1/lun1 -instance

and moidfy it if necesarry

Re: Moving RDM LUNs to new storage with SnapMirror

wswens42 — Wed, 04 Nov 2020 08:22:49 GMT

This looks like a good plan to me for moving it over to a new cluster. I am guessing you are using volume snapmirror for these?

Below are the steps for bringing up data access in a SAN environment after breaking a snapmirror. I am sure there will be some disk rescanning from the VMware side to get this going also.

https://docs.netapp.com/ontap-9/topic/com.netapp.doc.exp-sm-ic-fr/GUID-C7841261-B58F-4D13-BE5F-BE2BC67F2848.html?cp=7_7_1_1

SAN environment:

Map the LUNs to the appropriate initiator group to make the LUNs in the volume available to the SAN clients.
For iSCSI, create iSCSI sessions from the SAN host initiators to the SAN LIFs.
On the SAN client, perform a storage re-scan to detect the connected LUNs