> but if a disk fails you'll have to go into a read-only mode during the rebuild and deal with various hurdles in getting it rebuilt. I can't say for sure that

> but if a disk fails you'll have to go into a read-only mode during the rebuild and deal with various hurdles in getting it rebuilt. I can't say for sure that this never happens, but that's certainly not been the failure mode for any of the drive failures my btrfs RAID1 has experienced. I don't think I've ever needed to reboot or even remount my filesystem, just replace the failed drive (physically, then in software). But I always have more than two drives in the filesystem, so a single drive failure only puts a fraction of my data at risk, not everything.