btrfs send 3.11 vs 3.12
Hi
Sending snapshots incrementally started to fail on the 3.11 kernel on my system after I once booted with 3.12 and did the incremental send of a snapshot. After when I booted back to 3.11 I can no longer send the snapshots incrementally based on the last one sent (I could still send based on the last one sent from 3.11), although booting again to 3.12 I can send me fine again.
It this intenteded ?
best,
Signature · 2 lines
Miguel Negrão http://www.friendlyvirus.org/miguelnegrao
Am 23.01.2014 10:22, schrieb Miguel Negrão:
Quoted 9 lines
Hi
Sending snapshots incrementally started to fail on the 3.11 kernel
on my system after I once booted with 3.12 and did the incremental send of a snapshot. After when I booted back to 3.11 I can no
longer send the snapshots incrementally based on the last one sent
(I could still send based on the last one sent from 3.11),
although booting again to 3.12 I can send me fine again.
Quoted 4 lines
It this intenteded ?
best,
Hi Miguel,
btrfs guarantees backward compatibility since 3.13(?), but never guaranteed forward compatibility. So it is not yet supported to mount the fs with an older kernel once it was mounted with a newer one. Especially when using features that are under heavy development right now.
Also try to keep your kernel up to date (3.13 is out since a few days)
Joshua
Quoted 10 lines · Miguel Negrão
Hi
Sending snapshots incrementally started to fail on the 3.11 kernel on my system after I once booted with 3.12 and did the incremental send of a snapshot. After when I booted back to 3.11 I can no longer send the snapshots incrementally based on the last one sent (I could still send based on the last one sent from 3.11), although booting again to 3.12 I can send me fine again.
It this intenteded ?
This is definitely not intended, I will look into why this is happening. Thanks,
Josef
Quoted 2 lines · Joshua Schüler
btrfs guarantees backward compatibility since 3.13(?), but never guaranteed forward compatibility.
Isnt' this the opposite way? Forward means that old fs will be mountable on a newer kernel.
I don't know what you mean by 'backward compatibility is guaranteed since 3.13'. There are some features that get turned on automatically if used for the first time, but not all of them prevent mounting on an older kernel. Exmaple is the uuid tree, "generation v2" that's been introduced with send. Older kernel ignores the changes and newer kernel is usually able to recognize that the data are not all-ok and recovers itself or allows the user to do so manually.
Quoted 2 lines
So it is not yet supported to mount the fs with an older kernel once it was mounted with a newer one.
That's right, but in practice is not that bad.
Quoted 1 line
Especially when using features that are under heavy development right now.
Which features do you mean? Once a feature is introduced, the format and incompatibility bits should not change. The code may change, and does of course, but always in a compatible way.
Em 23-01-2014 14:19, Josef Bacik escreveu:
Quoted 11 lines · Miguel Negrão
Quoted 9 lines
Hi
Sending snapshots incrementally started to fail on the 3.11 kernel on my system after I once booted with 3.12 and did the incremental send of a snapshot. After when I booted back to 3.11 I can no longer send the snapshots incrementally based on the last one sent (I could still send based on the last one sent from 3.11), although booting again to 3.12 I can send me fine again.
Quoted 3 lines
Quoted 1 line
It this intenteded ?
This is definitely not intended, I will look into why this is happening. Thanks,
Great, thanks. The error:
Quoted 7 lines
miguel@miguel-MacBookPro:~$ sudo btrfs send -p /mnt/ssd/backups/@-2014-01-22-11\:29/ /mnt/ssd/backups/@-2014-01-23-17\:51/ | sudo btrfs receive /media/miguel/backup/backups/@ At subvol /mnt/ssd/backups/@-2014-01-23-17:51/ At snapshot @-2014-01-23-17:51 ERROR: could not find parent subvolumemiguel@miguel-MacBookPro:~$ ls -l /media/miguel/backup/backups/@ total 0
...
Quoted 1 line
drwxr-xr-x 1 root root 358 Jan 22 11:31 @-2014-01-22-11:29
Don't know if it's relevant, but I'm already mounting the filesystem with subvolid=5 since was an issue too:
Quoted 1 line
sudo mount -o subvolid=5 -U f2e4e4d3-2d8e-4764-a818-de9176405c4b
/mnt/ssd
best,
Miguel
Signature · 2 lines
Miguel Negrão http://www.friendlyvirus.org/miguelnegrao
Hi,
please take a look into this thread:
http://www.spinics.net/lists/linux-btrfs/msg30573.html
I had a similiar problem and got the answer + a fix from the list.
Regards,
Felix
Quoted 45 lines · Miguel Negrão
Em 23-01-2014 14:19, Josef Bacik escreveu:
Quoted 11 lines · Miguel Negrão
Quoted 9 lines
Hi
Sending snapshots incrementally started to fail on the 3.11 kernel on my system after I once booted with 3.12 and did the incremental send of a snapshot. After when I booted back to 3.11 I can no longer send the snapshots incrementally based on the last one sent (I could still send based on the last one sent from 3.11), although booting again to 3.12 I can send me fine again.
Quoted 3 lines
Quoted 1 line
It this intenteded ?
This is definitely not intended, I will look into why this is happening. Thanks,
Great, thanks. The error:
Quoted 7 lines
miguel@miguel-MacBookPro:~$ sudo btrfs send -p /mnt/ssd/backups/@-2014-01-22-11\:29/ /mnt/ssd/backups/@-2014-01-23-17\:51/ | sudo btrfs receive /media/miguel/backup/backups/@ At subvol /mnt/ssd/backups/@-2014-01-23-17:51/ At snapshot @-2014-01-23-17:51 ERROR: could not find parent subvolumemiguel@miguel-MacBookPro:~$ ls -l /media/miguel/backup/backups/@ total 0...
Quoted 1 line
drwxr-xr-x 1 root root 358 Jan 22 11:31 @-2014-01-22-11:29
Don't know if it's relevant, but I'm already mounting the filesystem with subvolid=5 since was an issue too:
Quoted 1 line
sudo mount -o subvolid=5 -U f2e4e4d3-2d8e-4764-a818-de9176405c4b
/mnt/ssdbest,
Miguel--
Miguel Negrão
http://www.friendlyvirus.org/miguelnegrao