I have a RAID backup pool of HDDs, which I do not want to spin up at boot, as I use it only for backup tasks.
Is there a manual way, to set spin down in UNRAID? Thru GUI I see 15 min. as the least amount of time after the spin down takes place.
Maybe I can set the time manually to 1min or so?
Thx in advance!

I am on V 6.12.15

I'm afraid, you cannot prevent the pool to spin up on boot time.

This is, because UNRAID needs to check out, if all configured drives are available and in working condition.

You can set spin down time for every disk seperately (go to the "start" page, click on a single drive and set the time for something else but "standard" (all standard-setted drives use the central spin down time, here you can override it for a single drive))

But less than 15min is not available, and also not really usefull too. Spinup/down wears out the drives too. Some "Enterprise" type drives even hate it and break ealier. Also the spinup/down feature is implemented by a cron job which runs every 15mins or so. Starting it more often will produce more stress and consume more energy.

Keep in mind that a real RAID(Z?) pool needs to be treated as a single drive. It makes no sense for individual settings because in every read or write action all drives are involved (in UNRAID arrays only the actually used data drive and maybe the parity drive(s) are involved. Other members can keep on sleeping)

So I think, in your situation the setting is useless (but of course you can still set other drives to standard setting and all array drives to 15mins)

Ask yourself: Does it really matter if some disks are spinning for 15 min after an array start before the inbuilt spin down processes kick in?

If not, leave it be.

If it does matter, there's resources on the forum for triggering the spindown via script you could adapt for your needs, and you could use user script plugin to trigger after an array start and/or when any backup scripts finish.

Thx guys for the reply.

Okay, so I might stick on the 15 min. on the pool drives then. It is not RAIDZ it is btrfs RAID5 as I do not need the ZFS features here.
Therefor I have a Truenas server running.
I need the pool only for a cross backup of my existing truenas work folders.

These backups run over nigth, so I only need the pool up on that time.
I do not use the pool at all or work from it, it is only a safety backup on another device.

I thought I could set it somehow, that the disks are not on at boot, as UNRAID is able to hot swap / hot plug, I thought there could have been an option for that.

Thanks anyway for the replies!

@tjb_altf4

Do you have a link to the scripts by hand? I searched quickly, but did not find the source so far.

45 minutes ago, derpuma said:

Do you have a link to the scripts by hand? I searched quickly, but did not find the source so far.

Take a look at this thread (including the highlight post), or search for other scripts in the forum using "hdparm" as a keyword

https://forums.unraid.net/topic/20449-spin-down-spare-drive/#findComment-188344

Edited July 21, 2025Jul 21 by tjb_altf4

1 hour ago, derpuma said:

it is btrfs RAID5

Friendly reminder that btrfs raid5/6 are considered experimental and unsafe for actual use.

1 hour ago, derpuma said:

, as UNRAID is able to hot swap / hot plug,

Unraid does NOT support hot swap/hot plug.

Perhaps you are thinking of the Unassigned Devices plugin that DOES support this for drives it manages.

10 minutes ago, Kilrah said:

Friendly reminder that btrfs raid5/6 are considered experimental and unsafe for actual use.

Thanks, yes I know that. Is it really that bad? What would you recommend then?
ZFS might not be an option, as my System is mainly a VM Server where I work from and I need the RAM for my VMs.

The pool should only act as another security backup of my truenas server.
And as written: I am still on Unraid 6 latest Version, as UNRIAD 7 broke my macOS VMs booting up and I did not have the time right now, to fix these problems.

23 minutes ago, itimpi said:

Unraid does NOT support hot swap/hot plug.

Perhaps you are thinking of the Unassigned Devices plugin that DOES support this for drives it manages.

Sorry, that I was not precise. I meant stopping the array and then hot swap/plug! Of course a running pool or array does not like swap or plug of running drives. My bad!

38 minutes ago, derpuma said:

ZFS might not be an option, as my System is mainly a VM Server where I work from and I need the RAM for my VMs.

You don't need lots of RAM for ARC. Can set it to the max of 256MB and go ahead on your way, with potentially lower performance but that's likely not going to matter for backup use.

4 hours ago, Kilrah said:

You don't need lots of RAM for ARC. Can set it to the max of 256MB and go ahead on your way, with potentially lower performance but that's likely not going to matter for backup use.

So... I tried the ZFS RAIDZ with 3x 10TB HDD today, but unfortunately it seems to be very slow, esp. compared the the BTRFS RAID5. I set it up with standard settings, no special config, with only a minimum RAM setting. I have 64 GB in my Server, while I was using my VM with allocated 48GB RAM, copying files seemed to be very slow.
I use a 10Gb Ethernet Connection on both machines, my Truenas and Unraid Server and with ZFS RAIDZ files of aprox. 1TB took significantly more compares BTRFS RAID5.

In my actual array, I have only one NVME of 2TB, where all the system files, appdata, isos, etc. are stored.
My VMs are on a second 2TB NVME, a unassigned device, where I boot my VMs from.

My thinking now is, to actually use the Array possibilities from Unraid and put the 3x 10 TB HDDs in there where one acts as a parrity.

Question is, if I create a new blank config, how can I restore my settings (apps, VM settings, etc.) which are then on the previous array NVME, which then becames a unassigned disk too?

What is the best way to use it then, when I want the array to spin down also, when no backup job is running. So basically Uraid should not use the array when I work on the system with my Virtual machines!

I really need no redundancy or security for my VM images, as they backup over to my truenas server.

Does the array spin down, if these files stay there but non of these directory contains files, the VMs use?



I guess performancewise the Array would be the best bet?

Here is a little overview how have set it up the disk now as my daily VM workstation:

tbh, if everything is regularly backed up, just smash it in a raid0 config unless you need the uptime.
I've got a btrfs raid0 (3x hdd) config for my downloads that has been running for 4 years, but nothing irreplaceable or not backed up though!

I hear you and yes, stripping through the disks will definitely benefits speed, but I'd like at least a little bit of redundancy.
I will test a few scenarios and see what fits best.