Hello Unraid community!

 

I really hope you can help me out. I've tried attaching as much information as possible to this post. If you need any more information, please tell me and I will update the post accordingly.

 

## My Setup
I've been running Unraid v7.0.1 for about 7-8 months and have been very satisfied with it. My array consists of:
- 16x 20TB data drives
- 2x 20TB parity drives
- Total array size: 320TB

 

## The Issue
I've mounted my entire array to an Ubuntu 24.04.2 LTS VM using VirtioFS. However, I'm noticing a significant discrepancy in reported free space:

- Unraid dashboard shows 185TB free
- Ubuntu VM shows only 172TB free (using `df -Th`)

 

That's approximately ~12TB of "missing" free space, which seems excessive for normal overhead. 

 

Is this expected behavior for VirtioFS mounts?

 

## Mount Configuration
- Created a share named `vmdata` in Unraid
- Share settings: `Virtiofs Mode`, `User:vmdata` for "Unraid Share Mode"
- Ubuntu VM mounts via `/etc/fstab` entry: `vmdata /data/mount virtiofs defaults 0 0`

 

## Screenshots and Logs
Array status from Unraid Main tab showing 320TB total with 185TB free:

 

My Ubuntu VM is showing different free space:

➜  ~ df -Th /data/mount
Filesystem     Type      Size  Used Avail Use% Mounted on
vmdata         virtiofs  295T  124T  172T  42% /data/mount

 

### Additional Logs
I've attached comprehensive diagnostic logs to help troubleshoot this issue:

- Full Unraid diagnostic logs (attached to post)

 

- Full `lsblk` output (Unraid OS): 

https://logs.notifiarr.com/?25c8ca9014dc6d19#F971spXoWs5W3zCmVit5ScSfrsxfkkeHVXTS8N3EXzLB

 

- Full `df -Th` output (Unraid OS):

https://logs.notifiarr.com/?7503c1897084ff40#7X2ajmC6vyKNZdzsYfk1hWpUNGNtVp9m5Vvm1dvg1DCM

 

- Ubuntu VM XML configuration: 

https://logs.notifiarr.com/?bb9887c3a4f2cb4a#DenZ7LFdqkJm5K7Lc4SgAUpm4aS2L6jmzsS3oP9sp2hh

 

- VM logs from Unraid OS:

https://logs.notifiarr.com/?a5458d695e993f90#5ZTjDyJ32AQtirfVRRmACCyt9NW1rkvMgbXkB6pZ8Fdq

 

- Full `lsblk` output (Ubuntu VM):

https://logs.notifiarr.com/?b5d44327407193ad#HaAXDNc5MRY4KghupnVsFVjAfQ1TyB5zEDY82x61qstR

 

- Full `df -Th` output (Ubuntu VM): 

https://logs.notifiarr.com/?f76070f711795c9a#48Q54QC6K8jAukpN5igHYj7KxkcAhtuyHJXQYezXGQ6T

 

Any insight into whether this space discrepancy is normal or if there's a configuration issue would be greatly appreciated!

 

Thanks in advance for your help.

tower-diagnostics-20250307-1921.zip

I solved it - I'm an idiot. The Unraid GUI shows in TB, while the df on the VM uses TiB.