Getting another drive for as a backup?

[alphaod]

Dilemma here:
I had a drive go funny in my RAID; I don't know what happened, but it turned itself off and spun back up. I got a bunch of warnings about a failing drive and then I tested the drive. That was about 4 months ago. It has been running fine ever since until today. Another hiccup you could say. No SMART errors or anything. I don't even see anything in the logs. Problem is I'm worried it will fail without notice than them my RAID will be in reduced mode.

The drives I have are a generation old, but they still sell for a lot; so do I get a backup drive just in case? I'm at a dilemma because the drive I would need is still like $190 for 300GB (VelociRaptor)! That's just ridiculous. I will be upgrading to SSDs in the future (when prices come down a bit more), but right now this is workhorse.

Thoughts?

 

[Hellhammer]

Does it have to be VelociRaptor? If I recall correctly, you are running RAID 5, aren't you? One of the drives failed and now you're running it without the "backup drive", right?

It's my hangover day so sorry if my questions sound stupid, brains are a bit slow today

 

[alphaod]

If one drive fails I'll be running off of parity data which means it will be really slow. Plus there is a high risk of data loss should another drive fail or the parity is calculated wrong.

 

[nanofrog]

Leave what you have in it, but get another drive the same capacity or larger as a spare for the set (any enterprise HDD; it doesn't have to be a Velociraptor). Making it a Hot Spare will automatically rebuild if you've the physical space to do install it.

If not, you'll have to swap it out if a disk goes, mark it as a spare, and then the card will begin automatic recovery.

BTW, current MLC SSD's aren't suited for parity based arrays ("hidden" partition for parity data will have a high write amplification given it's only a fraction of the total capacity).