Failover Cluster - Cluster Shared volume usage high and expanding

Question

Hi,

So I have a faliover cluster with a few CSV volumes, however one seems to keep having the space filled up with no seemingly reasonable explanation.

the volume is 10TB in total, and is currently showing 941GB free however if i get all the sizes of the VHDx files on that CSV it comes to 8.12TB (so there surely should be 1.8TB free?) with it decreasing albeit slowly, daily. I have checked the actual byte files of each of the vdhx files and they arent increasing. there are no servers with snapshots on that volume either.

during backups using Veeam the storage does get used up more but it then recovers that back

any suggestions please?

Answer 1

Hi,

Thanks for your posting!

Firstly, I would like to check if the backup volume through Veeam is the volume that you have problem with. Then, based on your descriptions, it seems that you have data deduplication enabled when you backup your folders through Veeam. If so, you will find this blog helpful:

https://serverfault.com/questions/895703/size-on-disk-smaller-than-capacity-but-no-free-space

(Please note: Information posted in the given link is hosted by a third party. Microsoft does not guarantee the accuracy and effectiveness of information.)

In addition, this issue may occur if malicious or unauthorized access to an NTFS volume where large files or a high quantity of small files are secretly copied has occurred. This is a normal issue so don't freak out. You can follow the guidance in the article to troubleshoot your issue, to see if the guidance is helpful:

https://learn.microsoft.com/en-us/troubleshoot/windows-server/backup-and-storage/disk-space-problems-on-ntfs-volumes

Thanks for your support!

BR,
Joan

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Answer 2

thanks, turns out moving the CSV to a different owner sorted it out