topic Re: Best practice to migrate VMFS LUNs using Volume Snapmirror maintaining consistant LUN in ONTAP Discussions

Best practice to migrate VMFS LUNs using Volume Snapmirror maintaining consistant LUN

SUNIL_DAGAR — Thu, 05 Jun 2025 05:55:44 GMT

Hi Team,

I am planning to migrate over 100 VMFS LUNs using Volume Snapmirror to DR site on a new netapp controller. Can someone

suggest on the best practices to be used for a consistent LUN.

I will be doing a Vol Snapmirror to move VMFS LUN, but need to check the steps with you all for successfull remapping of those VMFS LUNs

at the destination VC.

Secondly, I am using same Volume Snapmirror method to replicate SQL LUNs to DR site & map those LUNs using SnapDrive for Windows.

But while using Connect Disk inside SnapDrive at destination, its throwing error as "" Unable to find a Snapshot copy containing a consistent LUN to restore""

Can someone help me on these two things.

Thanks.

Re: Best practice to migrate VMFS LUNs using Volume Snapmirror maintaining consistant LUN

radek_kubka — Mon, 19 Aug 2013 10:42:56 GMT

while using Connect Disk inside SnapDrive at destination, its throwing error as "" Unable to find a Snapshot copy containing a consistent LUN to restore""

I can pick this one up:

Connect Disk is meant to mount a LUN clone, so this is not for migration really. Once you've completed SnapMirror replication, break it, make destinations writeable & map LUNs to your hosts, rescan disks in Windows - SnapDrive should pick them up.

Re: Best practice to migrate VMFS LUNs using Volume Snapmirror maintaining consistant LUN

SUNIL_DAGAR — Mon, 26 Aug 2013 07:29:36 GMT

Thanks Radek for your inputs, but after couple of troubleshooting, I have got the solution for the second issue for inconsistent LUN copy.

My findings are :- When we replicate LUN to DR site using Snapmirror, & then try to mount to servers at DR site using SnapDrive for Windows, it would give us the above error as "" Unable to find a Snapshot copy containing a consistent LUN to restore"". Even if you do a Snapmirror Update, that also doesn't help.

Solution:- Once the LUN is Snapmirrored to DR site, first we need to use Update SnapMirror option available in SnapDrive, so that the final replication update is done using Snapdrive & thereafter you can connect that respective LUN to server using Snapdrive.

Steps:- Before Connecting Disk at DR site, select the said LUN & go to Actions --> Update SnapMirror. This option (Update SnapMirror) will not come, if you select a wrong LUN.

Once the update is done, then you try option Connect Disk, this worksssss..

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However, I am still looking for steps for VMFS LUN replication, as I am getting Signature issues while adding the LUN to DR site VC. While using the option " Use the exisiting Signature", the LUN gets added easily to VC at DR site, but it doesn't get automatically added to all the servers in that Cluster. I need to manually add those LUNs to each server in Cluster individually. But this is tiresome, as I need to map all 30--40 LUns to all 16 servers in Cluster manually. I cannot use Resignaturing the LUNs, as that requires many more settings inside the individual VMs inside as well...

Thanks ...

Any alternate or script or solution to this would be appreciated.