You got it! A write to the bad sector should cause the drive to re-map the bad sector. Not all drives do this. My drives (ST118202LC with EMC firmware B801) required me to change an option in the firmware to allow this to occur. I wish md could do this automatically! It would save a lot of down time. Guy -----Original Message----- From: linux-raid-owner@xxxxxxxxxxxxxxx [mailto:linux-raid-owner@xxxxxxxxxxxxxxx] On Behalf Of Michael Hardy Sent: Thursday, June 03, 2004 3:34 PM To: linux-raid@xxxxxxxxxxxxxxx Subject: raid5 + smartctl + uncorrectable read error + single-block-resync ? I've got smartd running (great tool: http://smartmontools.sf.net) and it just alerted me to an unreadable sector in one drive on a software raid5 array I have (linux kernel 2.4.18, I believe, I know its old) smartctl is capable of telling me exactly what LBA on the drive is unreadable, and I was reading this, which indicates it would be possible to remap that single block: http://cgi.cse.unsw.edu.au/~neilb/me/SoftRaid/01084418693 ...but I'm guessing that's just an idea, since its from May 13th 2004 and there a couple of indications of kernel hacking in it ("maintain a list of bad blocks", check thresholds, work on the recovery thread, etc) Is there any motion to get raid to implement this? If there is, I guess my only input (I'm a sysadmin level hacker, not a kernel hacker) would be to say - there should be some interface for external utilities to "educate" the linux raid module that a specific disk has a specific sector going bad. That way you could script smartd to take the results of a failed offline SMART test and send the bad LBAs to the raid module for read tests and resync Oh, and I want a pony. ;-) I couldn't resist asking that, since this is basically a gigantic feature request In the meantime, I guess logically failing the drive and re-adding it is the only way to remap the sectors, right? -Mike - 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 - 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
