I recently set up Unraid, but I noticed that my HDD never spins down at all.
I have a 64GB SSD as cache and a 2TB HDD connected via USB as the only drive in my array.
I know people dislike USB drives, but I never had this problem on my Ubuntu server before, the drive would always spin down after a few minutes.

 

Things I have done:
1. Stopped all docker containers and disabled docker and VM in settings (no VMs running)
2. In Settings > Disk Settings > Default spin down delay: 15 min, on the disk itself it is set to default so it is the same (15 min)
3. Installed Open Files and File Activity plugins, noticed that there is no read/write operation on the disk drive
4. Restarted the system, stopped the array, restarted the array, tried again
5. Moved appdata, system and domains share to cache SSD.

 

Interestingly, immediately after rebooting, I can spin down the drive manually, but it spins up again after a few seconds. After that, I can no longer spin down the drive, not even manually by clicking the green dot.

I'm lost. There is nothing accessing the hard drive, why doesn't it spin down? It used to work on Ubuntu, but since I installed Unraid it doesn't work anymore. Any help would be appreciated.

I have more or less the same setup and I'm experiencing exactly the same issue.

I have a 512GB SSD as cache and a 5TB external USB HDD.

No VM running.

 

Appdata, domains, system on cache

Only one Share with plain data on the HDD array

 

- No spindown of the USB HDD possible automated or manually

- I can even spin down the cache for a few seconds till file access, but ext. HDD does not spin down at all

- Stopped all dockers, disabled Docker and VM in Settings

- Checked with file activity plugin and could not see any activity there

- Multiple reboots

 

The USB drive just does not spin down. I wanted to learn a bit about Unraid and planned switching and 4 more harddisks were planned to be added in the final setup. But as this is still a personal server that will be untouched 90% of the day having 5 disks running 24/7 is just a NoGo and I'm already trying to find a solution for days without any luck.

Is the USB drive an Unassigned Device?

No - it's not an unassigned device.

 

I just tried to spin down the disk via terminal with hdparm and it works flawlessly.

Both, standby -y and sleep -Y spin down the disk immediately

 

root@MyUnraid:/dev# hdparm -y /dev/sdb

/dev/sdb:
 issuing standby command
SG_IO: bad/missing sense data, sb[]:  f0 00 01 00 50 40 00 0a 00 00 00 00 00 1d 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

1 hour ago, Hanswurst said:

it's not an unassigned device.

USB not recommended for array or pools for many reasons.

21 hours ago, Hanswurst said:

No - it's not an unassigned device.

 

I just tried to spin down the disk via terminal with hdparm and it works flawlessly.

Both, standby -y and sleep -Y spin down the disk immediately

 

root@MyUnraid:/dev# hdparm -y /dev/sdb

/dev/sdb:
 issuing standby command
SG_IO: bad/missing sense data, sb[]:  f0 00 01 00 50 40 00 0a 00 00 00 00 00 1d 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

Same for me. Manual spin down with this command actually works: smartctl -s standby,now /dev/sdX

I found someone with a similar problem here:

 

Of course, doing this manually every time is not an option. But I don't know why Unraid can't do it itself.

20 hours ago, trurl said:

USB not recommended for array or pools for many reasons.

I'm sorry, but this doesn't make sense to me. Neither Proxmox nor Ubuntu have a problem with my exact setup, only Unraid cannot spin down the USB drive.

This makes it seem like it is an Unraid related problem. It would be great if this could be investigated, rather than bashing on USB and doing nothing. Many people with NUC or other small servers don't have enough SATA ports, if any. Other operating systems don't have this problem.