FAS 8200 is not synchronize with RHEV 4.2 host ( NOt showing correct storage space)

[Naveen007]

HI ,

SUB :ISSUE    : Correct LUN/Volume space is not showing in Netapp storage 

We have FAS 8200 storage ontapt 9.4 version .when we delete space from host (RHEV4.2) ,it is not reflecting in netapp storage

Coneectivity : FC protocol 

Kindly suggest solution to resolve this issue 

[Trubida]

Do you have space allocation enabled on the LUN?  If not, enable space allocation on the LUN so that OnTap is notified when a delete occurs on the host.

https://library.netapp.com/ecmdocs/ECMP1196784/html/GUID-6AD84908-041A-497D-95A7-BB6AFDD1B282.html

[paul_stejskal]

Keep in mind you have different layers:

1) Aggregate has a WAFL file system physically on the disks.

2) FlexVol has a WAFL file system virtually laid out inside the aggregate.

3) A LUN is created as a flat file within the FlexVol and presented to the host.

4) The host then writes a file system on top of that (NTFS, EXT, VMFS, etc.).

When you free up space on the host, that is done on layer 4, which is the host operating system. It won't reflect on the layers above it. You can enable SCSI_UNMAP, which is a SCSI feature where instead of just marking blocks free on the host OS, it actually sends disk zeroing commands to ONTAP, which then will punch holes in certain blocks of the LUN. Once that is done, then most of the space will be reclaimed.

Also, keep in mind LUNs and FlexVols can be thin or thick provisioned, so it may reserve all the space depending on how you configure it.

[RajeshPanda]

@Naveen007  can you pleasereview the recommendeation provided by our Expert and let us know if you need any further asistance?

[Naveen007]

Hi,

We are workin with Netapp tech team and red-hat team ,issue is still nor resolved