hard drive controllers

[Skirge01]

Originally Posted by Taddeusz

At least with RAID 5 parity is interleaved over all the drives. Drives can't necessarily be wasted on parity.

If we're comparing apples to apples, drive space is being "wasted" (i.e. not utilized for storing user accessible data) in both scenarios. With RAID 5, you lose the equivalent of one drive for parity. With duplication, you "waste" an identical amount of data to what you are storing. If you fill a 500GB drive and have duplication on, you "wasted" a 500GB drive.

Originally Posted by Taddeusz

Because if one of the drives fails that data can be recreated. If you're on a simple striped array with no parity or duplication you've lost everything unless you have a recent backup.

First off, the issue I have with RAID 5 is that if you have more than one drive failure before the array can be rebuilt, you then lose everything.

Second, a striped array (aka RAID-0) doesn't even belong in this discussion because it's not even RAID. Talk about an oxymoron. It's missing the "R" piece, so it should be called AID! ;D At least with FlexRAID you have that redundancy in the form of parity.

[Taddeusz]

Originally Posted by Skirge01

If we're comparing apples to apples, drive space is being "wasted" (i.e. not utilized for storing user accessible data) in both scenarios. With RAID 5, you lose the equivalent of one drive for parity. With duplication, you "waste" an identical amount of data to what you are storing. If you fill a 500GB drive and have duplication on, you "wasted" a 500GB drive.

IMHO, space used for parity isn't wasted space. It may not hold data per se but it is necessary to protect from downtime during a drive failure.

Originally Posted by Skirge01

First off, the issue I have with RAID 5 is that if you have more than one drive failure before the array can be rebuilt, you then lose everything.

That is true for any kind of redundancy that protects from a single drive failure. I don't know the likelihood of that actually happening but regardless of whether or not you have a RAID array you should be making regular backups anyway... right?

Originally Posted by Skirge01

Second, a striped array (aka RAID-0) doesn't even belong in this discussion because it's not even RAID. Talk about an oxymoron. It's missing the "R" piece, so it should be called AID! ;D At least with FlexRAID you have that redundancy in the form of parity.

Now you're just trolling. Notice I never referred to it as such because a striped array provides no redundancy.

[S_M_E]

Oddly enough, I *just* had a drive failure. It was a pooled drive, not the system drive, and it was an old, small, 250G (1 of 2 that size), used drive that has been running 24/7 for about 3 years. It started the "Click o' Death" and threw up warnings that the drive was missing. I removed it and rebooted, no more errors and no lost files. I still have 1.35T free space.

[Skirge01]

Originally Posted by Taddeusz

IMHO, space used for parity isn't wasted space. It may not hold data per se but it is necessary to protect from downtime during a drive failure.

And, I was offering MHO in a joking fashion as to how I perceived it and was ready to let this thing die. When I first brought it up, I even mentioned how emotional some people get about this topic. So, here we are.

Originally Posted by Taddeusz

That is true for any kind of redundancy that protects from a single drive failure. I don't know the likelihood of that actually happening but regardless of whether or not you have a RAID array you should be making regular backups anyway... right?

Backups are for data that you can't afford to lose and/or can't replace. So, backing up my DVD rips does not make sense. If I use duplication for them, I'll need about 20 extra hard drives. With FlexRAID or RAID-5, I only need one more. IMHO, 19 additional hard drives is a waste.

Originally Posted by Taddeusz

Now you're just trolling. Notice I never referred to it as such because a striped array provides no redundancy.

As I said, I jokingly made a comment that we're both "wasting" space (notice that I used quotation marks in almost all those statements) and was ready to let it go at that. I wasn't the one who brought up striping, anyway. The fact that you didn't call it what it's known as in the computer industry doesn't change what it is commonly referred to.

This will be my last post on the subject. If we get back to useful discussion I'll chime in again.