Convert RAID 5 to RAID 6 while reducing array size

Hi,
I'm trying to convert a 6 device raid5 into a raid6. The 6th device was added into the Raid 5 by mistake instead of a grow operation to convert it into a RAID 6. As such the md device is not being used beyond the size that it had when it was a 5 device raid5.

Can this be done in a single grow step by specifying the reduced size (--array-size=xx) and new layout (l=6)?

Thanks,
Anshu--
To unsubscribe from this list: send the line "unsubscribe linux-raid" in
the body of a message to majordomo [at] vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Anshuman Aggarwal [ Sa, 07 Mai 2011 21:25 ] [ ID #2059247 ]

Convert RAID 5 to RAID 6 while reducing array size

Hi,
I'm trying to convert a 6 device raid5 into a raid6. The 6th device was added into the Raid 5 by mistake instead of a grow operation to convert it into a RAID 6. As such the md device is not being used beyond the size that it had when it was a 5 device raid5.

Can this be done in a single grow step by specifying the reduced size (--array-size=xx) and new layout (l=6)?

Thanks,
Anshu--
To unsubscribe from this list: send the line "unsubscribe linux-raid" in
the body of a message to majordomo [at] vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Anshuman Aggarwal [ Sa, 07 Mai 2011 21:50 ] [ ID #2059248 ]

Re: Convert RAID 5 to RAID 6 while reducing array size

On 07/05/2011 20:50, Anshuman Aggarwal wrote:
> Hi,
> I'm trying to convert a 6 device raid5 into a raid6. The 6th device was added into the Raid 5 by mistake instead of a grow operation to convert it into a RAID 6. As such the md device is not being used beyond the size that it had when it was a 5 device raid5.
>
> Can this be done in a single grow step by specifying the reduced size (--array-size=xx) and new layout (l=6)?

Yes it can, with mdadm 3.1.x and a suitably recent kernel. You will need
a backup file on another drive, the same as you did to reshape your
RAID5 from 5 to 6 devices. If you have grown your filesystem, you will
need to shrink it again BEFORE attempting the reshape.

Cheers,

John.

--
To unsubscribe from this list: send the line "unsubscribe linux-raid" in
the body of a message to majordomo [at] vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
John Robinson [ Mi, 11 Mai 2011 17:49 ] [ ID #2059328 ]
Linux » gmane.linux.raid » Convert RAID 5 to RAID 6 while reducing array size

Vorheriges Thema: [PATCH] Update documentation for sync_min and sync_max entries
Nächstes Thema: Problems creating MS-RAID1: "device .. not suitable for anystyle of raid array" / "De