Hi, i've got an interesting btrfs subvolume problem which i can't understand... Maybe someone here can give me a tip because i think that's only a user error... I had a root btrfs on / and made a subvolume some month ago for my home on /home (i think cwd was / and i used "btrfs subvolume create /home"). On friday i wanted to try an update of my distribution, so i created a snapshot on /snapshots/20110902 (cwd was / and i entered "btrfs subvolume snapshot / /snapshots/20110902). Today i realized that my update failed, so i did "btrfs set-default 257 /" (257 is the id of the snapshot from friday)... When i rebooted, the trouble began. The mounted "home" subvolume was empty (even if mounted) and the new root from today which i used before trying the set-default seems to be lost. Ok, not the main problem... The snapshot from friday was mounted correctly on boot as root. The directory /snapshots/20110902 is empty but it is still listed as subvolume. My "home" was also empty but still listed as subvolume. I tried to remove the subvolume, i tried to remove the directory, both not working. Then i tried to "mount -o subvolumeid=256 /dev/mapper/root /home" (id of home subvol) and the content of my home is back... My questions are: 1. where is the "original" root from today morning before i did set-default? Lost? 2. why can't i do "mount -o subvolume=home /dev/mapper/root /home" anymore? To be more exact, i can, but why is it empty and why is it working when i enter the subvolume id? 3. I am now using the snapshot /snapshots/20110902 but what is /snapshots/20110902 now and why is it still listed? It's empty? 4. can i now delete the snapshots/20110902 or will that drop my current active working root? 5. can i rename snapshots, e.g. the snapshots/20110902 or "home" to "home-20110905"? 6. is my btrfs filesystem broken now and should i recreate the whole thing or is it safe to use it? Bye Björn -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
