How to un degrade RAID10.

How to un degrade RAID10.

[ibm-main]

I see I'm not the only one to flounder with this. Btrfs v0.19 on
openSuSE 11.3-RC1 (2.6.34-9-default).
I created a RAID10 across 4 partitions - worked fine. Unmounted it and
zeroed one complete partition (as in of=/dev/sda8). Remounted degraded,
looked around, data seemed safe.
Attempted to remove sda8 from the array, but got an ioctl=1. Hmmm.

Did a (normal, non-RAID) mkfs on the partition, then attempted to add it
back as per the wiki. Won't mount without the degraded option even
though the 4 partitions are accepted o.k, and a re-balance worked.
The array now reports as 5 devices with #2 (the original slot for sda8)
now vacant - dare I say "missing". It reports as "*** Some devices missng"
This seems counter intuitive to me. Suggestions ?.

Re: How to un degrade RAID10.

[Tomasz Torcz]

On Mon, Jun 21, 2010 at 03:43:02PM +1000, ibm-main@tpg.com.au wrote:
> Did a (normal, non-RAID) mkfs on the partition, then attempted to add it
> back as per the wiki. Won't mount without the degraded option even
> though the 4 partitions are accepted o.k, and a re-balance worked.
> The array now reports as 5 devices with #2 (the original slot for sda8)
> now vacant - dare I say "missing". It reports as "*** Some devices missng"
> This seems counter intuitive to me. Suggestions ?.

  You can pass "missing" to "btrfs device delete".

-- 
Tomasz Torcz              ,,If you try to upissue this patchset I shall be seeking
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