On Tue, 24 Nov 2009 02:36:37 +0100 Kasper Sandberg <postmaster@xxxxxxxxxxx> wrote: > On Tue, 2009-11-17 at 09:47 +1100, Neil Brown wrote: > > On Mon, 16 Nov 2009 16:00:38 +0530 > > <senthilkumar.muthukalai@xxxxxxxxx> wrote: > > > > > We face this problem in our NAS product where we handle RAID5. > > > In the below mentioned scenario, when RAID5 is rebuilding after > > > adding a disk, we reset the power. > > > Ideally when the system comes up, the RAID5 should have accepted > > > the disk but not in our case. > > > We get the 'kicking the non-fresh disk from array' message with > > > the boot message. > > > In our RAID init script we run 'mdadm -- Examine -- scan', > > > followed by 'mdadm --assemble'. > > > Could you pls help me to understand why this disk is being thrown > > > out? > > > > It is because the metadata being used (v0.90) does not have the > > ability to record that a device is partially recoverred. It can > > only record that a device is either a full member of the array, or > > is not a member of the array. So until the recovery completes, the > > metadata only records that the device is not a member of the > > array. So when you restart, you find that the device is not a > > member of the array. > > > > > > > What could be the solution? > > > > Use 1.x metadata. e.g. add > > --metadata=1.1 > > to your --create command. > > 1.x metadata is able to record that a device is only partially > > recovered. So when the array is restarted the device will be > > included and recovery will continue. > > Might it be possible to upgrade metadata without having to recreate > the array? It isn't currently possible. It would not be too hard to implement a conversion from 0.90 to 1.0 metadata, but I have not concrete plans to provide this. NeilBrown -- 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
