Will drives last longer if kept on 24/7 or server turned on every 3 days

[DisplayNerd]

My UNRAID server isn't really used that often and doesn't support s3 sleep so to save power I wrote a script to turn it off if it's not used for 30 min (or VMs are on). The script runs from 3-7am. I wrote a script on my Raspberry Pi to wake it at 6pm every 3 days (for backups). When it's running the drives don't spin down. Everything works well. If my family does use the NAS or the Pi wakes it for backups/maintinence it will be on from poweron to 3am and then shutoff. It seems to be a better idea then spinning the drives down when unused because I don't need to have the server on for anything else and nobody uses the NAS before 6. However, I heard shutting servers down and starting back up might be worse than spinning down/starting up. How bad is shutting off vs spinning down and is it really not worth the power savings? Also, is shutting off/spinning drives once every 3 days (or once a day if my family uses it a lot) going to kill my hard drive sooner than keeping the hard drives running 24/7 or spinning them down once every 2+ days?

[Jerky_san]

Technically if you keep them spinning they will never "cool" thus there is a less chance for startup failure like heads crashing and stuff. I'll say in my line of work with massive amounts of drives in servers. We've had servers that were never powered off for years. Simply rebooted without cycling the drives. I remember one time we finally powered this one machine off and a bunch of its drives died at the same time lol. The motors simply didn't have enough power to start them cold anymore.

 

I'll say I just let them spin.. the power savings isn't worth it to me but others see if differently. If you don't really use it much then you don't use it much. I leave mine on 24x7 though even when I'm not. I have a 2990wx and it can eat some juice..

[DisplayNerd]

Right. I get that keeping drives spinning won't allow the motors to spin down/spin up and thus won't cause problems that way if the drives are kept spinning in perpetuity. However, since this is a Home Server I do have to turn it off during storms etc. and my battery backup isn't strong enough to keep the server on for hours during a power outage, so ultimately the spin up/spin down scenario will happen. Your solution is the best in data centers because as you said the drives will never cool down, because data centers can afford to keep their servers running all the time with large battery backups. I'm trying to find a way to put the least strain on my hard drives considering (even if I keep them spinning up the majority of the time) I might have to spin them down every now and then. I don't really care about power costs, and I could spin down the drives rather than shut off the system if that will prolong drive life. But if keeping them spinning 24/7 will actually prolong drive life longer than spinning them down once every couple days, I'm definitely open to that. I'm just trying to find the best solution. However, the reality is I can't keep them spinning 24/7 365 in a home environment. That being said, is it worse on the motor to spin up once every ~3 days or keep drives spinning 3 days straight?