I've added a drive to my unRaid box. It is not part of the protected array and doesn't seem to ever spin down. This makes me think that the spin down delay is both controlled by the OS and only includes protected disks. Am I correct in this assumption?

 

If so, could the spin down delay be changed to affect all the drives in the system? Or could someone provide a clue on how I can spin down a drive that is not part of the array?

 

Thanks

I've added a drive to my unRaid box. It is not part of the protected array and doesn't seem to ever spin down. This makes me think that the spin down delay is both controlled by the OS and only includes protected disks. Am I correct in this assumption?

Almost Correct.  They are controlled by the emhttp process.  I don't think they are part of the Linux kernel itself, but you are correct in that it only affects disks assigned in the array.

If so, could the spin down delay be changed to affect all the drives in the system?

Not very likely, not by Lime-technology at least.

Or could someone provide a clue on how I can spin down a drive that is not part of the array?

Easy

Use the hdparm command to set the drive's own spin-down timer.  (It is has one, and most do, it will spin up/down on its own)

The manual page is here: http://linux.die.net/man/8/hdparm

 

The specific command is

hdparm -S nnn /dev/DDD

(where DDD = the three letter device designation of your drive)

and nnn is a number described as in the manual page for hdparm...

nnn = 0 = timeouts disabled.

nnn = Values from 1 to 240 specify multiples of 5 seconds, yielding timeouts from 5 seconds to 20 minutes.

nnn = Values from 241 to 251 specify from 1 to 11 units of 30 minutes, yielding timeouts from 30 minutes to 5.5 hours 

          To get a spin-down time of 1 hour you would use 242.

nnn = A value of 252 signifies a timeout of 21 minutes.

nnn = 253 sets a vendor-defined timeout period between 8 and 12 hours.  (Good luck trying to find out the time for your drive)

nnn = 254 is reserved.  (Could create a black hole, could reformat the internet, could do absolutely nothing)

nnn = 255 is interpreted as 21 minutes plus 15 seconds.

 

Note that some older drives may have very different interpretations of these values.

 

So, put a line in your config/go script like this to get a 1 hour timeout for /dev/sdh (as an example)

hdparm -S 242 /dev/sdh

Thanks

You are welcome.

 

Oh yes, there are some options to the hdparm command that are very dangerous and will corrupt your data on a drive (some even force a failure). 

Don't use any of them.  The manual page gives lots of warnings.

 

Joe L.

Thanks Joe for the helpful reply. Since you suggest putting this in the go script, the setting is not persistent between reboots, right?

Thanks Joe for the helpful reply. Since you suggest putting this in the go script, the setting is not persistent between reboots, right?

I do not think it is persistent... But it would really depend on the drive manufacturer....  Easiest to set it each time you reboot.

 

Joe L.

I added a new drive to the array, but couldn't find any means of adding it to the array? Even after stopping the array it is not possible to add it to array as the assignement slots for new drives won't list it. It is a precleared and properly marked drive and I have 4.5...

wrong topic