Checking individual drive state
I've recently built a smallish RAID5 box as a storage area for my home network, using mdadm. However, one of the drives will not remain in the array for longer that around two days before it is removed. Readding it to the array does not throw any errors, leading me to believe that it's probably a problem with the controller, which is an add-in SATA card, as well as the other drive connected to it failing once. I don't know how to scan the one disk for bad sectors, stopping the array and doing an fsck or similar throws errors, so I need help in determining whether the disc itself is faulty. If the controller is to be replaced, how would I go about migrating the two discs to the new controller whilst maintaining the array? Thanks in advance Tom Bradshaw - To unsubscribe from this list: send the line unsubscribe linux-raid in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: Checking individual drive state
On Sun, 5 Nov 2006, Bradshaw wrote: I've recently built a smallish RAID5 box as a storage area for my home network, using mdadm. However, one of the drives will not remain in the array for longer that around two days before it is removed. Readding it to the array does not throw any errors, leading me to believe that it's probably a problem with the controller, which is an add-in SATA card, as well as the other drive connected to it failing once. I don't know how to scan the one disk for bad sectors, stopping the array and doing an fsck or similar throws errors, so I need help in determining whether the disc itself is faulty. try swapping the cable first. after that swap ports with another disk and see if the problem follows the port or the disk. you can see if smartctl -a (from smartmontools) tells you anything interesting. (it can be quite difficult, to impossible, to understand smartctl -a output though. but if you've got errors in the SMART error log that's a good place to start.) If the controller is to be replaced, how would I go about migrating the two discs to the new controller whilst maintaining the array? it depends on which method you're using to assemble the array at boot time. in most cases if these aren't your root disks then a swap of two disks won't result in any troubles reassembling the array. other device renames may cause problems depending on your distribution though -- but generally when two devices swap names within an array you should be fine. you'll want to do the disk swap with the array offline (either shutdown the box or mdadm --stop the array). -dean - To unsubscribe from this list: send the line unsubscribe linux-raid in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: Checking individual drive state
dean gaudet wrote: On Sun, 5 Nov 2006, Bradshaw wrote: I don't know how to scan the one disk for bad sectors, stopping the array and doing an fsck or similar throws errors, so I need help in determining whether the disc itself is faulty. try swapping the cable first. after that swap ports with another disk and see if the problem follows the port or the disk. you can see if smartctl -a (from smartmontools) tells you anything interesting. (it can be quite difficult, to impossible, to understand smartctl -a output though. but if you've got errors in the SMART error log that's a good place to start.) I don't think SMART output is that hard to understand. And checking the entire drive for errors is as easy as 'smartctl -t long /dev/drive' usually. If it is SATA as you say, you may need to put a '-d ata' in there. Wait for however long it says to wait, then do a 'smartctl -a /dev/drive' and you should see the self test log at the bottom. Did it finish? If not, there are bad sectors. If there are bad sectors, you should google the string 'BadBlockHowTo' to see if you can clear them (after failing the drive out of the array) Note that this won't tell you anything about cables or controllers or power or anything else that could and may be wrong. It's just for the drive media and firmware. -Mike - To unsubscribe from this list: send the line unsubscribe linux-raid in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
