<div class="gmail_quote">On Tue, Dec 21, 2010 at 11:06 PM, Jim Kinney <span dir="ltr"><<a href="mailto:jim.kinney@gmail.com">jim.kinney@gmail.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;">
<p>Raid 5,6 is a waste of time. When one fails a second failure is likely before recovery can finish. Raid 10, thanks to cheap drives, is the best bet. If you're totally paranoid, do the mirror in triplets.</p></blockquote>
<div>I would agree that RAID 5 is a total waste of time. For a very small array (say, 5 disks) I'd say that RAID 6 is acceptable, *IF* you are relatively proactive about preventing catastrophic failure. Again, remember that RAID is not a backup solution, just one to add reliability, and even RAID 5 is going to be more reliable than no RAID at all (or striped, but not mirrored, RAID). Making sure that drives are periodically rotated, that they are all different ages, that the array is protected from power surges and outages, making sure that the host system is protected from power surges and outages, are all required elements, or you _will_ have corruption at some point.</div>
<div><br></div><div>What I do after installing a RAID 5 or 6 setup (well, a RAID 6 setup; I don't use RAID 5 at all) is I get it going with five or so drives, and then every three months I replace one drive. Then every six months I'll replace one drive. I expect more failures than a standard setup because of the additional activity that happens when using RAID {5,6}, particularly in the regular consistency/health checking process.</div>
<div><br></div><div> --- Mike</div></div>