Michael, That's great news. Well done. ext4 works just fine for most cases. If you wish to experiment I might suggest more work on your part (just what you need, right?) by using btrfs for smaller file systems (perhaps just root, maybe /var, /bin etc.) but try installing zfs for large file systems (user, tmp, whatever might get a little larger). I do this on ubuntu, and btrfs works great on a 60 Gig root partition, and zfs for home, vms, iso, etc. I think zfs works on Suse (or maybe mini-Suse; don't remember), and if your machine has enough ram, it can be quite snappy (for low ram machine for zfs turn off compression, dedup, etc.).
Or just use ext4, make lots of backups, and experiment later. I don't have a preference on file systems in general, but I do know they each (usually) excel at different things. Btrfs is very nice to have on linux, because it is already in many kernels by now, and can work with limited ram. I do have to say the ability to create, send and receive incremental snapshots saves a lot of time and work, and as far as I know only btrfs and zfs do this without using something like lvm (maybe you do this now with xfs and lvm? If so, I think you can also make snapshots with lvm and ext4). I would not give up on btrfs yet. You might consider using btrfs for detachable backup disks. Gordon On Tue, Jan 31, 2017 at 3:30 PM, Michael Born <michael.b...@aei.mpg.de> wrote: > Thank you all for your help. > > Magically, btrfs-find-root worked today. (I attached the steps at the end) > I don't think I changed anything. The btrfs-progs version is still 4.1 > because I tried different tagged versions (starting from 4.9) from the > cloned git repo. > > The btrfs-find-root on the working / of my computer (Intel 3750K@4.2GHz > on a Samsung 850EVO) took several seconds. > btrfs-find-root on the 60GB dd-image (on the same computer on a 960EVO > ssd) loop device took 6 minutes until it stared asking me "do you want > to keep going on ? (y/N/a): We seem to be looping a lot on..." questions. > I answered them with yes. The command was finished then 1 minute later. > - just for a reference, if somebody wonders, how many days one has to wait. > > Strangely, the second run of btrfs-find-root finished differently. The > first run did not mention the snapshots. > This also confirms my suspicion, that the tool is working far from > perfectly. > > It's absolutely clear that I came here because of my stupidity (making a > dd backup of my live btrfs root partition), but it really frightens me > how quickly (2 days reading/trying wiki/blog/mailing list solutions) I > came to the point of having to grep text files by its contents from my > image.dd. > I don't run database computer center, so I'm not relying on the nice > btrfs features. But, for my next clean installation I will rather use > ext4 just because there are tons of forensic/recovery tools available > for the worst case. > Thank you again for your quick and helpful answers. > > Cheers, > Michael > > PS: I now just took the NetworkManager settings to not have to enter all > Wifi details when traveling. So, it was really mostly an exercise. > > > linux-2bf5:/home/michael # losetup -f > /dev/loop0 > linux-2bf5:/home/michael # losetup /dev/loop0 ./20170126_sda2root.dd > > > linux-2bf5:/home/michael # btrfs fi show > Label: none uuid: 779e9c04-be4b-4a45-9fc2-000acca5549d > Total devices 1 FS bytes used 19.02GiB > devid 1 size 118.16GiB used 25.03GiB path /dev/sda4 > > Label: none uuid: 91a79eeb-08e0-470e-beab-916b38e09aca > Total devices 1 FS bytes used 44.22GiB > devid 1 size 60.00GiB used 60.00GiB path /dev/loop0 > > linux-2bf5:/home/michael # > > > linux-2bf5:/home/michael/btrfs-progs # ./btrfs fi show > Label: none uuid: 779e9c04-be4b-4a45-9fc2-000acca5549d > Total devices 1 FS bytes used 19.02GiB > devid 1 size 118.16GiB used 25.03GiB path /dev/sda4 > > Label: none uuid: 91a79eeb-08e0-470e-beab-916b38e09aca > Total devices 1 FS bytes used 44.22GiB > devid 1 size 60.00GiB used 60.00GiB path /dev/loop0 > > btrfs-progs v4.1 > linux-2bf5:/home/michael/btrfs-progs # ./btrfs-find-root /dev/sda4 > Superblock thinks the generation is 14210 > Superblock thinks the level is 1 > Found tree root at 12232638464 gen 14210 level 1 > Well block 12173475840(gen: 14209 level: 1) seems good, but > generation/level doesn't match, want gen: 14210 level: 1 > Well block 12081152000(gen: 14198 level: 1) seems good, but > generation/level doesn't match, want gen: 14210 level: 1 > linux-2bf5:/home/michael/btrfs-progs # ./btrfs-find-root /dev/loop0 > Couldn't read tree root > Superblock thinks the generation is 549995 > Superblock thinks the level is 1 > Well block 32794263552(gen: 550001 level: 1) seems good, but > generation/level doesn't match, want gen: 549995 level: 1 > linux-2bf5:/home/michael/btrfs-progs # > > > > linux-2bf5:/home/michael/btrfs-progs # ./btrfs restore -t 32794263552 > /dev/loop0 /home/michael/btrfs/ > parent transid verify failed on 32794263552 wanted 549995 found 550001 > parent transid verify failed on 32794263552 wanted 549995 found 550001 > Ignoring transid failure > We seem to be looping a lot on > /home/michael/btrfs/var/log/audit/audit.log.4, do you want to keep going > on ? (y/N/a): y > We seem to be looping a lot on > /home/michael/btrfs/var/log/audit/audit.log.3, do you want to keep going > on ? (y/N/a): We seem to be looping a lot on > /home/michael/btrfs/var/log/audit/audit.log.2, do you want to keep going > on ? (y/N/a): y > We seem to be looping a lot on > /home/michael/btrfs/var/log/audit/audit.log.1, do you want to keep going > on ? (y/N/a): We seem to be looping a lot on > /home/michael/btrfs/var/tmp/kdecache-miborn/plasma_theme_openSUSElight_v0.5.kcache, > do you want to keep going on ? (y/N/a): y > Error writing: 28 No space left on device > Error copying data for /home/michael/btrfs/var/cache/cups/ppds.dat > Error searching /home/michael/btrfs/var/cache/cups/ppds.dat > Error searching /home/michael/btrfs/var/cache/cups/ppds.dat > Error searching /home/michael/btrfs/var/cache/cups/ppds.dat > We seem to be looping a lot on > /home/michael/btrfs/var/tmp/kdecache-miborn/plasma_theme_openSUSElight_v0.5.kcache, > do you want to keep going on ? (y/N/a): > linux-2bf5:/home/michael/btrfs-progs # > > > linux-2bf5:/home/michael/btrfs-progs # ./btrfs restore -t 32794263552 > /dev/loop0 /home/michael/btrfs/ > parent transid verify failed on 32794263552 wanted 549995 found 550001 > parent transid verify failed on 32794263552 wanted 549995 found 550001 > Ignoring transid failure > We seem to be looping a lot on > /home/michael/btrfs/var/log/audit/audit.log.4, do you want to keep going > on ? (y/N/a): y > We seem to be looping a lot on > /home/michael/btrfs/var/log/audit/audit.log.3, do you want to keep going > on ? (y/N/a): We seem to be looping a lot on > /home/michael/btrfs/var/log/audit/audit.log.2, do you want to keep going > on ? (y/N/a): y > We seem to be looping a lot on > /home/michael/btrfs/var/log/audit/audit.log.1, do you want to keep going > on ? (y/N/a): We seem to be looping a lot on > /home/michael/btrfs/var/tmp/kdecache-miborn/plasma_theme_openSUSElight_v0.5.kcache, > do you want to keep going on ? (y/N/a): y > We seem to be looping a lot on > /home/michael/btrfs/var/tmp/kdecache-miborn/plasma_theme_openSUSElight_v0.5.kcache, > do you want to keep going on ? (y/N/a): Skipping snapshot snapshot > Skipping snapshot snapshot > Skipping snapshot snapshot > Skipping snapshot snapshot > Skipping snapshot snapshot > Skipping snapshot snapshot > Skipping snapshot snapshot > Skipping snapshot snapshot > Skipping snapshot snapshot > Skipping snapshot snapshot > Skipping snapshot snapshot > Skipping snapshot snapshot > Skipping snapshot snapshot > Skipping snapshot snapshot > Skipping snapshot snapshot > Skipping snapshot snapshot > linux-2bf5:/home/michael/btrfs-progs # > > > > > Am 31.01.2017 um 03:30 schrieb Lakshmipathi.G: >>> >>> Does someone on the list know if ext3/4 data recovery tools can also >>> search btrfs data? That's another option. >>> >>> Gordon >>> >> ext3/4 (or other) data recovery tools can help, if they have generic >> file search mode not tied to specific file systems. >> Have a look at ext4magic >> http://ext4magic.sourceforge.net/ext4magic_en.html - It said to have >> file carving option. Though I'm not sure whether it accepts non-ext file >> system. >> >> And there is https://github.com/Lakshmipathi/extcarve (supports >> different FS) but I never updated it in years, so skeptical about it. I >> guess this https://github.com/sleuthkit/sleuthkit may be your best bet. >> >> If want to take recovery tool route - remember to backup original dd >> image file. >> ---- >> Cheers, >> Lakshmipathi.G > > -- > 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 -- 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
