Refs Formated Volume Connection from 2019 to 2025 Server

[govi]

Hi All,

Hope everyone doing good.

Has anyone tried adding ReFS formatted volume from Windows Server 2016 to 2025? Anyone faced RAW issue after attaching to Server 2025?

Is it safe to attach iSCSI drive which is formatted in Refs format to Windows Server 2025. We have migrated from VMware to Hyper-V and installed new backup Server 2025. 2016 version is bit old and right time to update. 2025 Server is fresh installation.

I am bit afraid to connect iSCSI Drive to Server 2025 since it might corrupt entire volume and I might loose the backup Data. We are not going to use server 2016 server so we are not going to connect back this iSCSI drive and I am 100% it will corrupt the data since meta data will be upgraded to higher version and Refs does not have backward compatibility.
Although we have backup Copies and live data. Just don't want to risk it.

Thanks,

Govi

[HannesK]

Hello,
I don't remember that specific scenario but I personally would do a snapshot of the iSCSI volume on the storage side and then try it out. If it fails, open a support case with Microsoft. With the storage snapshot there is a "way back".

Best regards
Hannes

[govi]

Hi All,

After making snapshot. I manage to connect iSCSI Drive to Windows Server 2025 without data corruption.

Disconnected iSCSI drive Windows Server 2016 and made sure that Windows Server 2016 cannot connect again to iSCSI Volume again. Thats the time corruption of Volume will happen.

Connected iSCSI drive to new Windows Server 2025 and brought back volume online.

Thanks,

Govi