[NBLUG/talk] RAID on the cheap?

[Lincoln Peters]

Well, it happened again.  The hard disk that I got via warranty to
replace the hard disk that failed, that I got via warranty to replace
the other hard disk that failed, has failed.  I think I'll be able to
get this one replaced via the warranty again, but I'm getting rather
paranoid at this point, so I'm trying to figure out a way to protect my
data using RAID without spending more any money than I need to.

My current plan is as follows:
* One internal IDE (parallel ATA) 250GB hard drive.
* Two external USB2.0 250GB hard drives, or two external IDE hard drives
in USB-to-IDE enclosures.  Additional hard drives may be added later.

I plan to use software RAID-4, with the internal IDE drive as the parity
drive (since it will get the most activity, I'd put it on the fastest
interface).  I suspect that in this case, RAID-5 (with parity
distributed among each drive) would offer lower performance, as any
write operation to the array would require a write to each drive, which
would cause all of them except the internal to constantly compete for
bandwidth.

The machine is running Debian/testing with a 2.6.7 kernel.  It has two
onboard USB 2.0 ports.

I am not inclined to purchase a hardware RAID controller, as all the
ones I've seen that support RAID-4 and/or RAID-5 are too expensive for
my budget.


Has anyone ever tried anything like this?  Any pitfalls you've
encountered, either with software RAID or external USB drives (or both)?
Any reason(s) I should go for FireWire drives (or enclosures) instead?

---
Lincoln Peters
<sampln at sbcglobal.net>

A bird in the hand makes it awfully hard to blow your nose.