Hello, I have 3 pools on my Truenas Scale and wanted to do some power management with HDD Standby and Advanced Power Management (APM). Pool 1 = 1 SDD - Stripe - For apps Pool 2 = 2x 4TB Ironwolf Pro - Mirror - Media storage and other big stuff Pool 3 = 3x 500GB Toshiba something - RAIDZ1 - Lots o…

From my personal (and small) experience, I have 2 pools, one of SSDs (2x1TB mirrored), and one of HDDs (5x4TB RAIDz1, with one additinal 1TB L2ARC SSD, and 2 of the HDDs used as spare for now, until I need more storage). I have set the SSDs with no power savings, as they are continuly used by conta…

Thanks, So if I were to put use standby on Pool3, what APM should I use on it? Level 1 - minimum power usage with spindown Level 128 - minimum power usage with no spindown

Level 1. If they do not spin down, usually, it is because you have the boot pool set on this pool. Move it to a safe pool of SSDs.

Do you mean that the “System Dataset” might be located on that pool (which then prevents it from spinning down) ?

Exactly. That one. However, I understood that if you loose the data of this dataset, it might get complicated, so it is preferable to have it on a mirrored (or redondant pool so you not loose it)

I’m by no means an expert, and maybe other gurus will chime in, but as far as I can tell the situation is this: The system dataset stores logs, statistics, and some service data (e.g., Samba DB), but no user data. If the pool is lost, it’s inconvenient but not critical – TrueNAS and your data pools …

I tried out this feature when I first built my Electric Eel system last year, and found that the drives did indeed spin down after the inactivity time, but they’d spin back up many times throughout the day, because TrueNAS runs frequent short SMART tests on the drives which can’t be disabled or dela…

[image] dwolsten: found that the drives did indeed spin down after the inactivity time, but they’d spin back up many times throughout the day, because TrueNAS runs frequent short SMART tests on the drives which can’t be disabled or delayed. I thought under the configuration for S.M.A.R.T. the…

Correct. I have been spinning down 100% HDDs that I look after. Never had an issue and I appreciate the savings in power, heat, etc. I really hope IX won’t take it away as this is simple standard Linux functionality.

Things to know before enabling 'HDD Standby' and 'Advanced Power Management'?

TrueNAS General

Krill September 6, 2025, 2:47pm 4

Seagate drives do not respond to the APM commands. You need to use Seachest to change the settings.

https://forums.truenas.com/t/hdd-errors-in-truenas-but-tests-passed-in-seagate-seatools/50965/6?u=krill

Topic		Replies	Views
HDD not going to Standby (spindown) anymore after update from 23.10.2 (Cobia) to 24.04.0 (Dragonfish) TrueNAS General SCALE	16	2409	December 27, 2024
HDD Sleep/Spindown/Standby TrueNAS General SCALE , Hardware	256	41481	September 5, 2026
TrueNAS 25.10.0 (Goldeye) is spinning up my disks every 90 minutes TrueNAS General SCALE , Community-Edition	11	1921	November 12, 2025
HDDs are all the time active TrueNAS General SCALE	9	274	February 22, 2026
Cannot get disks to spindown TrueNAS General SCALE , Hardware	6	940	February 14, 2025

Things to know before enabling 'HDD Standby' and 'Advanced Power Management'?

Related topics