Hi Qu,
Unfortunately, single mode means no duplication.
And degrade mount only works for RAID level with
duplication(DUP,RAID1/5/6/10).
further to the below commit.
commit 95669976bd7d30ae265db938ecb46a6b7f8cb893
Btrfs: don't consider the missing device when allocating new chunks
in case of 2-disk RAID1 mounted with only one good disk, we would create
Single profile and actually the created single profiles are still
workable with one disk failed. And so the proposed patch below will let
single profile to be mount in this context..
[PATCH 23/23] Btrfs: allow -o rw,degraded for single group profile
to recover when missing disk is replaced balance convert can migrate
single profiles back to RAID1 profile.
Also your explanation for degraded is correct, I am ok to use a new new
mount option (like auto-reduced-profile ?) if needed / confusing.
Any comments / feedbacks are welcome.
Thanks, Anand
--
To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html