The best way to avoid a raid 5 failure is to use raid 10- Plus you get the added benefit of no write performance problems.<br><br><br><br><div class="gmail_quote">On Tue, Jan 3, 2012 at 12:41 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">Jim's RULE of RAID: NEVER, EVER INSTALL RAID DRIVES WITH SEQUENTIAL SERIAL NUMBERS!!! <br><br>If possible, avoid RAID drive purchases from the same supplier and manufacturer. <br>
<br>I was bit once by a RAID5 failure. The lesson I learned is to image ALL remaining drives before replacing the failed drive. <br>
<br>Google did research on drive failure rates and recover times and found that once a drive is larger than 500GB, a RAID5 system is a bad idea. The failure rate of similar age drives (even mixed version, model, etc.) was such that the array was likely to fail a second drive before the first failure had been recovered from. RAID6 only buys a bit more time as it requires a 3 drive failure for data loss. Based on that and my own experience, RAID 10 is the only stuff I use now. When the data ABSOLUTELY must be available, I use a 3 drive mirror spread across 3 different controllers (so, yes, software raid) so typically, the mobo controller and 2 additional cards. 12 drives in 4 stripes with 3 copies of each stripe makes me happy. It's an especially good setup for write seldom, read often servers. The write speed is not sufficient for high-write-throughput database stuff so I'd incorporate some SSD hardware for WAL stuff.<br>
<br><div class="gmail_quote"><div><div class="h5">On Tue, Jan 3, 2012 at 10:59 AM, Michael Trausch <span dir="ltr"><<a href="mailto:mike@trausch.us" target="_blank">mike@trausch.us</a>></span> wrote:<br></div></div>
<blockquote class="gmail_quote" style="margin:0pt 0pt 0pt 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div><div class="h5">
Well, all I am going to say is thank goodness I'm using RAID 6 and not<br>
RAID 5, or all would have been lost for me at the start of the year.<br>
<br>
I'll write more later, I learned that the Linux kernel is also not as<br>
great in handling certain things as it could be. :-/<br>
<br>
--- Mike<br>
<span><font color="#888888"><br>
--<br>
A man who reasons deliberately, manages it better after studying Logic<br>
than he could before, if he is sincere about it and has common sense.<br>
--- Carveth Read, “Logic”<br>
<br>
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<br></blockquote></div><span class="HOEnZb"><font color="#888888"><br><br clear="all"><br>-- <br>-- <br>James P. Kinney III<br><br>As long as the general population is passive, apathetic, diverted to
consumerism or hatred of the vulnerable, then the powerful can do as
they please, and those who survive will be left to contemplate the
outcome.<br>- <i><i><i><i>2011 Noam Chomsky<br><br><a href="http://heretothereideas.blogspot.com/" target="_blank">http://heretothereideas.blogspot.com/</a><br></i></i></i></i><br>
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