zGreenfelder wrote:
On Mon, Mar 4, 2013 at 11:20 AM, John Plemons john@mavin.com wrote:
Raid 10 is a mirrored stripped set of at least 4 driver. You get the best of both worlds, data speed and data back up..
yeah, that's the industry standard. he's asking you to go find and read http://en.wikipedia.org/wiki/Raid10#Near_versus_far.2C_advantages_for_bootab... wherein they mention that linux md devices can do what they call a raid 10 on 2 drives. and then details some of the reasons you might want to do such a thing.
I can't see any reason to go with the sorta raid 10 on only 2 drives. from that article, I'd the only sane choice for raid 10 on 2 drives is the 'far' config on SSD drives. but that's just my opinion. I don't think I'd ever pick raid10 on 2.
from the entry: "...copies of a block of data are "near" each other or at the same address on different devices or predictably offset: Each disk access is split into full-speed disk accesses to different drives, yielding read and write performance like RAID 0 but without necessarily guaranteeing that every stripe is on both drives"
which then some (and by murphy's rule will be the most critcal) will go from being raid 10 to raid0. and likely 0 on the drive that fails.
AHHH! I didn't read closely enough, and missed that lack of guarantee. Thanks, *that's* the kind of discussion I was looking for.
mark