Microsoft Virtualization Discussions
I provisioned thin-provisioned LUNs from my NetApp controller in Cluster mode to a Hyper-V server.
However, it seems like I can not reclaim space from this LUN on the storage end.
there is a command I can run on both ends to fix this anomaly if it were VMware. Is there a command I have to run on the storage end to fix this, or is it a bug with Microsoft Hyper-V?
LUN is thin-provisioned
Space reservation is enabled
Space allocation is enabled.
See The Solution
Follow the KB article:
How to verify whether SCSI UNMAP is enabled or disabled on a Windows host?
> fsutil behavior query disabledeletenotify
DisableDeleteNotify = 0 means in-band UNMAP is enabled for the host.
Hope this helps 🙏
View solution in original post
Just adding to the previous post, you also need to make sure that the space-allocation option is enabled on the LUN in ONTAP. This KB gives a little more detail: ONTAP and Windows SCSI unmap and space reclamation - NetApp Knowledge Base
One thing to highlight in the KB is that if you change the option on the LUN, you need to reboot Windows to see the change.