> On Thu, 30 Dec 2010 16:17:51 -0800 Mark Knecht <markknecht@gmail.com> wrote:
>
>> On Thu, Dec 30, 2010 at 4:16 PM, Mathias Burén <mathias.buren@gmail.com> wrote:
>> > On 31 December 2010 00:14, Mark Knecht <markknecht@gmail.com> wrote:
>> >> On Thu, Dec 30, 2010 at 4:12 PM, Mathias Burén <mathias.buren@gmail.com> wrote:
>> >>> On 31 December 2010 00:10, Mark Knecht <markknecht@gmail.com> wrote:
>> >>>> Hi,
>> >>>> What am I forgetting to do? I had a RAID1 using sd{a,b,c}3. I
>> >>>> stopped md3, removed the md3 line in /etc/mdadm.conf, deleted the
>> >>>> partitions using fdisk, and then created 5 new partitions using
>> >>>> sd{a,b,c,d,e}3 to get ready to do a 5 disk RAID6. The new partitions
>> >>>> are the same size as the old ones and located at the same sector
>> >>>> addresses.
>> >>>>
>> >>>> After rebooting, but before creating the new RAID6, I still see md3:
>> >>>>
>> >>>> mark@c2stable ~ $ cat /proc/mdstat
>> >>>> Personalities : [linear] [raid0] [raid1] [raid10] [raid6] [raid5] [raid4]
>> >>>> md6 : active raid1 sdb6[1] sdc6[2] sda6[0]
>> >>>> 247416933 blocks super 1.1 [3/3] [UUU]
>> >>>>
>> >>>> md3 : active raid1 sdc3[2] sdb3[1] sda3[0]
>> >>>> 52436096 blocks [3/3] [UUU]
>> >>>>
>> >>>> md5 : active raid1 sdc5[2] sdb5[1] sda5[0]
>> >>>> 52436032 blocks [3/3] [UUU]
>> >>>>
>> >>>> unused devices: <none>
>> >>>> mark@c2stable ~ $
>> >>>>
>> >>>>
>> >>>> What am I doing wrong or forgetting? I would like md3 to be totally
>> >>>> gone before I create a new md3 in it's place.
>> >>>>
>> >>>> Thanks,
>> >>>> Mark
>> >>>> --
>> >>>> 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
>> >>>>
>> >>>
>> >>> Erase the superblocks? Recreating partitions doesn't (usually) affect
>> >>> the data on the HDDs.
>> >>>
>> >>> // M
>> >>>
>> >>
>> >> Is erasing the superblocks a mdadm operation? I've not heard of that one before.
>> >>
>> >> Thanks,
>> >> Mark
>> >>
>> >
>> > Yes, see mdadm --misc. Like:
>> >
>> > mdadm --zero-superblock <device>
>> >
>> > // M
>> >
>>
>> Yes, just found that.
>>
>> Can I still use /dev/md3 safely even though it's no longer in
>> mdadm.conf? I suspect I can?
>
> That sentence doesn't make much sense to me, so I suspect some misunderstand
> is going on. So to be explicit:
>
> Use
> mdadm --zero-superblock /dev/sdc3 /dev/sdb3 /dev/sda3
>
> to remove from those devices any record that they are part of any md array.
>
> Does that clarify thing sufficienty?
>
> NeilBrown
