Re:Bcachefs Merged into the Linux 6.7 Kernel
by creatonez on Tuesday October 31, 2023 @06:05PM
(#38092062)
RAID1 in Btrfs is not entirely fine. It won't nuke your data and there is no write-hole issue, 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.
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Re:Bcachefs Merged into the Linux 6.7 Kernel
by wtallis on Tuesday October 31, 2023 @07:46PM
(#38092856)
> 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.
Re:Bcachefs Merged into the Linux 6.7 Kernel
by viraptor on Tuesday October 31, 2023 @08:46PM
(#38093293)
> if a disk fails you'll have to go into a read-only mode during the rebuild
That's not correct, you can rebuild online. The readonly mode is only relevant when you reboot during the failure and don't have the right options set on the volume.
But you totally can replace a live drive without affecting the availability.