Re: Simple Raid-1 setup question

["Majed B." <majedb@gmail.com>]

1) No need to sync if both disks are new (or have no data).
That can be accomplished using: --assume-clean

2) It shouldn't be a problem. If you still can't force mdadm, use dd
(be very sure you're writing to the correct disks!!)
dd if=/dev/zero of=/dev/sdx bs=10M count=1

That will write 10MB of zeros to the disk. It should corrupt any
filesystem laying there.

Remember to change the partition type to "FD" for RAID auto-detect.

Create your filesystem on the array after you create it & that's it.

On Fri, Nov 13, 2009 at 11:34 PM, Kurt Newman <kurt@lamer.org> wrote:
> My questions are as follows:
>
> 1) If you're creating a completely new array (e.g. raid-1) on new
> partitions that aren't formatted, do you still have to sync?  I'm having
> difficulty finding information on why and when a sync is needed.  I was
> under the impression a sync is only needed when there's existing
> information on one or more of the drives.
>
> 2) If there used to be information on each device, but has since been
> repartitioned, so that new partitions and a raid device can be
> created... is there any way to prevent mdadm from asking if you really
> want to create the array?  Using `--force' doesn't seem to help.
>
> mdadm: /dev/sda1 appears to contain an ext2fs file system
>   size=1464840K mtime=Fri Nov 13:04:09 2009
> mdadm: /dev/sdb1 appears to contain an ext2fs file system
>   size=1464840K mtime=Fri Nov 13:04:09 2009
> Continue creating array?
>
> As a side note, there really isn't an existing ext3 fs on it, but there
> used to be.  To re-use the device, I issued the following commands:
>  > parted -s /dev/sda mklabel msdos
>  > parted -s /dev/sda mkpart primary ext3 0 1500
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-raid" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>



-- 
       Majed B.
--
To unsubscribe from this list: send the line "unsubscribe linux-raid" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html