Just upgraded a MD RAID 5 box to 2.6.11 from 2.4.something. Found out one disk was failing completely, got a replacement from Maxtor. Neat. Replaced disk, rebooted.. Added the new disk to the array with 'raidhotadd'. MD started syncing. A couple of minutes into the process, it started *seriously* spamming the console with messages: ========================== Apr 22 01:47:00 linux kernel: ..<6>md: syncing RAID array md1 Apr 22 01:47:00 linux kernel: md: minimum _guaranteed_ reconstruction speed: 1000 KB/sec/disc. Apr 22 01:47:00 linux kernel: md: using maximum available idle IO bandwith (but not more than 200000 KB/sec) for reconstruction. Apr 22 01:47:00 linux kernel: md: using 128k window, over a total of 199141632 blocks. Apr 22 01:47:00 linux kernel: md: md1: sync done. Apr 22 01:47:00 linux kernel: ..<6>md: syncing RAID array md1 Apr 22 01:47:01 linux kernel: md: minimum _guaranteed_ reconstruction speed: 1000 KB/sec/disc. Apr 22 01:47:01 linux kernel: md: using maximum available idle IO bandwith (but not more than 200000 KB/sec) for reconstruction. Apr 22 01:47:01 linux kernel: md: using 128k window, over a total of 199141632 blocks. Apr 22 01:47:01 linux kernel: md: md1: sync done. ========================== Thought it had probably gone haywire and decided to start trashing my data, so pulled the plug and rebooted. When examining the log afterwards, I can see that the above messages repeat themselves. cat /var/log/messages | grep md | grep 'Apr 22 01:47:01' | grep 'sync done' tells me that the messages were repeated 12 times per second. The /var/log/messages file grew to 600kB before I pulled the plug. Noticed something strange during next boot: Linux failed to recognize one of the disks. Booted into Maxtor PowerMax and it said various weird things (seemed different each time) about the disk too. So decided to switch ATA cables on this disk, which made wonders - both PowerMax and Linux talks to the disk fine now. Now, when I boot the machine, the 6 disks in the array have these event counters, according to mdadm: sda1: 0.19704 (completely new, "blank" disk) sdb1: 0.19704 sdc1: 0.144 (but why?) sdd1: 0.19704 sde1: 0.19704 (this disk had the bad cable) sdf1: 0.19704 My questions now are (and yes, I know I had faulty hardware, but that's incidentally also the reason I use MD at all): 1. What's with the infinitely repeated md1: sync done messages? 2. Wouldn't the mentioned event counters cause MD to think that the totally blank disk /dev/sda1 has valid data, and that the disk with valid data (/dev/sdc1) does not next time it syncs? 3. How do I proceed from here, if I want to rescue my data? Best regards, many thanks for MD and all that :-). - 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
