On 4/16/13 6:35 PM, Adam Goryachev wrote: > Obviously, if they suffered a two disk [RAID 1] failure then they won't > be here asking for help will they :) Heh. Well, no, they won't if the disks are completely and permanently dead. (I know I'm starting to sound like a broken record, but "that's partly why we use three disks instead of two and make sure they don't all use the same company's firmware".) But complete disk death doesn't seem to be the normal failure mode. If the failure is spurious, as so many seem to be, and temporarily affects an array so that each disk has a different event count, that isn't a disaster under RAID 1. If worst comes to worst, you can pick one disk to use and pretend RAID doesn't even exist. You don't need to get the members to successfully sync into an array to read the data. But if each disk in a RAID 5 or RAID 6 array gets a different event count, or if the disks refuse to easily assemble into an active array for any other reason, all your data is inaccessible until you fix the RAID problem. I avidly read the details of every RAID 5 [and 6] disaster on the list, and almost every one would be trivially easy to fix under RAID 1, with no risk of complete data loss. It's heartbreaking. -- Robert L Mathews, Tiger Technologies, http://www.tigertech.net/ -- 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
