On Fri, 6 Aug 2004, Kanoa Withington wrote: > On Fri, 6 Aug 2004, Salyzyn, Mark wrote: > > Just reading the entire array should correct the bad blocks, so reverse > > the sense of the dd: > > > > dd if=/dev/md0 of=/dev/null bs=200b > > > > to find and replace the bad blocks (making the assumption that md works > > like the H/W RAID cards). > > In this case software RAID does not work like the H/W cards. Finding > an unreadable block that way in a software array would cause it to go > into a degraded state. if the disks support SMART (i.e. they're less than a few years old) then try running the smart long selftest... it can be done online and on many disks it will force sector reallocation (and produce a SMART log event so you know it happenned). get smartmontools and run "smartctl -a" to see info on your drive, and "smartctl -t long" to launch the long test. man page has more examples. i run smart long tests on each my disks once a week (staggerred over many nights)... see /etc/smartd.conf. -dean - 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