A problem:LUN usage rate >100%, how can reclaim sapce?

[ZZY_CAPTAIN]

Hi,I meet a problem,that is, from OnCommand System Manager, i see that there is a lun, 100.25% used,this lun is for VMware and thin provisioned, the volume included this lun has snapshots.

the reason i guess is, someone delete all files in this lun by vphere before and reuse the lun, now i closed the volume snapshot and deleted all snapshots,but the problem hasnot been solved, who can help?

[resqme914]

A quick search of this forum will show you a number of discussions on this subject.  Because LUNs are block-access devices, Ontap really has no way of "book-keeping" what the host is doing to space.  What you (or the server admin) should be concerned about is the host space utilization, not what System Manager is showing you.  Over time, lun space utilization will grow towards 100%.  If you're really concerned about this and you're using Snapdrive on the host, you can "reclaim" the space, but it's not normally necesssary.

[ZZY_CAPTAIN]

thanks for your respond!

I still have confusion about the space reclaim, if vmware or other hosts write too many data and then delete them, continuously, so the available space will be less and less, storage didnot konw which block is invalid and cannot auto reclaim space,  it seems unscientific and wasteful?

[resqme914]

Here are some links that might help you...

https://communities.netapp.com/blogs/luke/2011/09/09/vaai-in-vsphere-50-part-1

https://communities.netapp.com/message/2091#2091

http://www.netapp.com/us/media/tr3483.pdf

TR3483 section 4.1, "Host vs. Storage View" is especially relevant.