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

Reply via email to