Debugging no HDD spindown

TrueNAS General
1

I’ve enabled HDD spindown in the disks web page in the truenas front end, however, the disks are spinning. How to debug ?

thanks
Richard.

RAIDZ2
12 x Seagate IronWolf Pro 10TB nas - in one big pool
HP DL380e G8i dual 8 core xeon E5-2450 14 bay LFF
HP H220 9205-8i 2-Port SAS 6GB PCI-E 3.0 x8 HBA Host Bus Adapter Card
Solarflare SFC9100 Flareon 7000 Series dual 10Gb nic
TrueNAS-12.0-U5

2

Most Common Problem that prevents spin down is the system Dataset. It get’s placed on the first datapool that is created and writes logdata to the pool which then prevents the Disks from Spinning down. Relocate the system Dataset to your Boot SSD and your Disks should spin down

3

many thanks @LarsR that looks like it worked, well the lights on the disks dont seem to be coming on as much and it seems a bit quieter - is there a better way to know if the disks have spun down ?

4

I don’t know, i don’t spin down my disks and the general opinion for spin down is that the increased wear from spining up and down leads to faster disk failures. So i never bothered to learn more about disk disk spindown.

5

from shell (dont forget to change the * with your drive number):

camcontrol cmd ada* -a “E5 00 00 00 00 00 00 00 00 00 00 00” -r -

→ 50 00 00 00 00 00 00 00 00 FF 00
in the output the decimal position is what you need to check
FF: spinning
00: spin down

i think this works too:

camcontrol epc ada* -c status -P

→ PM0:Active or PM1:Idle(0xff)

for what is my experience (for a little period i try the spindown script provided by community), avoid spindown, there are more risks than benefit. A marginal power consumption/noise reduction compared to a greater wear of the disks (worst if spin up/down are high in the day), and the difficulty to program SMART tests (because, maybe only in my case using the script, disks not spinup automatically when the SMART is scheduled)