Quite the historian...
on
Hardware Bytes
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· Score: 2, Interesting
Hoo boy, the reviewer over at LANParty has really been around...
Since the introduction of optical mouse a couple of years ago, the technology has evolved many times already...
I had an optical mouse on my '286 - that would be back in '88 or '89, I think. It needed a goofy mousepad with gridlines on it, but just like the ones today, it didn't get gunked up and it worked pretty well. It's pretty pathetic to hear these "veterans" speak about hardware like they's seen a lot. Probably some snot-nosed 17-year-old who thinks Linus invented Unix a few years back...
RAID 10 can survive a second failure if it occurs in a different mirror group than the first failed drive. However, if two drives fail within the same mirror group, all you're left with is half of a striped array, which is useless.
That doesn't sound right to me. If you have a mirrored pair of striped sets with parity, you should be able to survive a either a failure in both sets (essentially losing parity in both, but not data), OR two drives failing in one set. If you lose two drives in one set, it's basically the same as losing one half of a mirrored pair of drives; you're left with the other half of the mirror - that's the whole point of mirroring.
In fact, you should be able to get through a triple failure - two drives in one set (which kills that set) plus one drive in the other set (so you lose parity).
Confusing, I know, but it seems like a significant oversight on the part of the author, when he's explaining the technology.
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Hoo boy, the reviewer over at LANParty has really been around...
Since the introduction of optical mouse a couple of years ago, the technology has evolved many times already...
I had an optical mouse on my '286 - that would be back in '88 or '89, I think. It needed a goofy mousepad with gridlines on it, but just like the ones today, it didn't get gunked up and it worked pretty well. It's pretty pathetic to hear these "veterans" speak about hardware like they's seen a lot. Probably some snot-nosed 17-year-old who thinks Linus invented Unix a few years back...
-HL
In the article, it states:
RAID 10 can survive a second failure if it occurs in a different mirror group than the first failed drive. However, if two drives fail within the same mirror group, all you're left with is half of a striped array, which is useless.
That doesn't sound right to me. If you have a mirrored pair of striped sets with parity, you should be able to survive a either a failure in both sets (essentially losing parity in both, but not data), OR two drives failing in one set. If you lose two drives in one set, it's basically the same as losing one half of a mirrored pair of drives; you're left with the other half of the mirror - that's the whole point of mirroring.
In fact, you should be able to get through a triple failure - two drives in one set (which kills that set) plus one drive in the other set (so you lose parity).
Confusing, I know, but it seems like a significant oversight on the part of the author, when he's explaining the technology.
-HL