Should I spin down the drives or keep them on when idle?

[someuser77]

Hello,
I have a FreeNAS 8.0.1 box with two Samsung 2TB HD204UI drives and I don't know if I should configure them to spin down when idle or not.
Currently I don't access the NAS very often, maybe once a day, so I just shut it down for the night or when I don't need it. I would like to know what is better for the drives in terms of life span?
To power them only when needed, to shut them for the night and spin them down when idle or just keep them on together with the box all day?
I found a couple of links that state that drives are better off being on forever and that powering them down increases the stress on the drives and should be avoided.
Is there any known best practice regarding home NAS?

 

[jgreco]

It kind of depends on the drives, but also your tolerance for replacing drives and higher electric bills.

Spinning drives up and down is indeed rough on the drives; the difference between spinning them down and powering them off is negligible in comparison.

What you don't want to be doing is spinning them up and down dozens or hundreds of times a day. However, a single daily cycle is well within the design considerations of most hard drives - these things are designed to be able to get stuck into somebody's PC, and most users do turn their PC on and off daily.

Spinning them up and down increases the chance of failure, the more you do it, the more likely to see an eventual failure.

Running them 24/7 also slightly increases the chance of failure, the longer you run them, the more likely to see an eventual failure.

Your best options are really to leave them powered off, continuously, or on and spun down, continuously. Of course those aren't too useful.

Leaving them on and having the NAS spin them up as needed is generally seen as the "easy" solution to this, but it will put your electric bill higher by some amount. Turning the NAS off as soon as you know you're done with it is also low risk, more work, but saves power.