I had no idea the odds were that bad. Time to switch to zfs... Russ ------Original Message------ From: Greg Freemyer Sender: linux-raid-owner@xxxxxxxxxxxxxxx To: Dawning Sky Cc: linux-raid@xxxxxxxxxxxxxxx Subject: Re: Disk I/O error while rebuilding an md raid-5 array Sent: Feb 8, 2010 7:04 PM > > PS, if in the end I have to build a new array, I'll probably go with a > raid 6 instead. Agreed, someone recently posted that for a raid-5 composed of 1TB drives the odds of a rebuild failure are 1 in 67 even if the remaining drives are within spec. (ie. the unrecoverable bit error rate is slowing succumbing to the ever increasing size of drives.) You have 500GB drives, but you have 3 left to rebuild from, so that's 1.5 TB your trying to read. I'm not sure how the original calculation was done, so your odds of failed rebuild were either 1 in 134 or about 1 in 42. Either not very good for something that is supposed to protect your data. Greg -- Greg Freemyer Head of EDD Tape Extraction and Processing team Litigation Triage Solutions Specialist http://www.linkedin.com/in/gregfreemyer Preservation and Forensic processing of Exchange Repositories White Paper - <http://www.norcrossgroup.com/forms/whitepapers/tng_whitepaper_fpe.html> The Norcross Group The Intersection of Evidence & Technology http://www.norcrossgroup.com -- To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html Sent from my Verizon Wireless BlackBerryÿôèº{.nÇ+?·?®??+%?Ëÿ±éݶ¥?wÿº{.nÇ+?·¥?{±þ¶¢wø§¶?¡Ü¨}©?²Æ zÚ&j:+v?¨þø ¯ù ®w¥þ?à2?Þ?¨èÚ&¢)ß¡«a¶Úÿÿûàz¿äz¹Þ?ú+?ù???Ý¢jÿ?wèþf
