I would like to setup unraid to only spin down disks when I tell it to.

 

What do I set the default wait time for a spindown to? Zero?

 

Do I have to disable the disks internal spindown timer?  If yes, is it the same command for all disks (I do it for a samsung that is not in the array)?

 

I am using Hitachi 2TB disks in the array.

The unRAID management console has a setting called "NEVER" on the settings page [http://tower/settings.htm].

 

I do not know if that will interfere with you trying to spin down the disks yourself. You may need to spin them down by issuing the spindown command using '/root/mdcmd'. There are several user-contributed scripts that have handled the issue. Hopefully someone who uses them or knows of them better will respond.

Do I have to disable the disks internal spindown timer? 

If yes, is it the same command for all disks (I do it for a samsung that is not in the array)?

Yes.  And, yes.

 

Once you set "NEVER" on the unRAID management console, that's it, unRAID won't meddle with spindowns. 

Spin them down yourself as you see fit with the hdparm command.  (Don't go through mdcmd!)

 

Is there meaningful downsides to never spinning down the disks? In terms of the long-term health of the disks?

Besides more wear on the bearings, more power usage, and more heat generated probably not.

Spin them down yourself as you see fit with the hdparm command.  (Don't go through mdcmd!)

Purko,

 

Why do you stress to not go through mdcmd?  If you've set the spin-down times to never, there is no reason I can see to not use the

/root/mdcmd spindown X

or

/root/mdcmd spinup X

commands?

 

And more importantly, if you've set the spin-down times to anything other than never, you MUST use the mdcmd spinup/spindown commands to keep emhttp's timers in sync.

 

Joe L.

Spin them down yourself as you see fit with the hdparm command.  (Don't go through mdcmd!)

Purko,

 

Why do you stress to not go through mdcmd? 

If you've set the spin-down times to never, there is no reason I can see to not use the

/root/mdcmd spindown X

If we set up unRAID not to be involved in any spin-down, there is no reason I can see to use mdcmd.

The command to spin down a disk is: `hdparm -y DEVICE`. 

Mdcmd uses hdparm, but it also does a bunch of other (unneeded in this case) things.

 

And more importantly, if you've set the spin-down times to anything other than never....

I am aware of that, but that's not the case we are discussing.

 

If you've set the spin-down times to never, there is no reason I can see to not use the

/root/mdcmd spindown X

The only one I can think of offhand is when checking for disk temperature.  It might think the drive is not spinning, and not report a temperature for the drive, when in fact the drive is spinning and a temperature reading could be provided.  In the same way, spinup groups are still potentially involved, and if it does not think the drives are already spinning it will issue unneeded commands.  These have nothing to do with the spin-down timer.

The only one I can think of offhand is when checking for disk temperature.  It might think the drive is not spinning, and not report a temperature for the drive, when in fact the drive is spinning and a temperature reading could be provided.  In the same way, spinup groups are still potentially involved, and if it does not think the drives are already spinning it will issue unneeded commands.

I have disabled my unRAID (4.5.4) from doing any spining up or down. (I have a good reason for that, but we'll get off topic). Whan disabled, it does not "think" anything about the drive status: it looks it up when needed, and behaves accordingly. If it finds the drive sleeping, it doesn't report temperature; if it finds the drive spinning, it gets its temperature. All works as expected.