Help to gain access to btrfsraid6 pool that won't mount
$ uname -a Linux thejay-srv03 4.0.0-040000-generic #201504121935 SMP Sun Apr 12 23:36:33 UTC 2015 x86_64 x86_64 x86_64 GNU/Linux
$ btrfs --version btrfs-progs v3.19.1
$ sudo btrfs fi show Label: 'roms03' uuid: b0025417-4045-4c63-a432-0625b7cc41ea Total devices 4 FS bytes used 2.67TiB devid 1 size 1.36TiB used 1.36TiB path /dev/sdz devid 3 size 1.36TiB used 1.36TiB path /dev/sdaa devid 4 size 1.36TiB used 1.36TiB path /dev/sdab *** Some devices missing
This pool is a btrfsraid6 pool
when trying to mount I get:
$ sudo mount -t btrfs -o recovery,ro /dev/sdaa /mnt/roms03
mount: wrong fs type, bad option, bad superblock on /dev/sdaa,
missing codepage or helper program, or other error
In some cases useful info is found in syslog - try
dmesg | tail or so$ dmesg -T|tail [Mon May 4 08:35:08 2015] BTRFS info (device sdz): enabling auto recovery [Mon May 4 08:35:08 2015] BTRFS info (device sdz): disk space caching is enabled [Mon May 4 08:35:08 2015] BTRFS: has skinny extents [Mon May 4 08:35:08 2015] BTRFS: failed to read chunk tree on sdz [Mon May 4 08:35:08 2015] BTRFS: open_ctree failed
What could I try to see if I can mount this pool and gain access to the data?
While I have a backup of the data, next time I may not, and I am trying to learn how to go about.
Quoted 33 lines · TheJay
$ uname -a Linux thejay-srv03 4.0.0-040000-generic #201504121935 SMP Sun Apr 12 23:36:33 UTC 2015 x86_64 x86_64 x86_64 GNU/Linux$ btrfs --version btrfs-progs v3.19.1$ sudo btrfs fi show Label: 'roms03' uuid: b0025417-4045-4c63-a432-0625b7cc41ea Total devices 4 FS bytes used 2.67TiB devid 1 size 1.36TiB used 1.36TiB path /dev/sdz devid 3 size 1.36TiB used 1.36TiB path /dev/sdaa devid 4 size 1.36TiB used 1.36TiB path /dev/sdab *** Some devices missingThis pool is a btrfsraid6 pool
when trying to mount I get:
$ sudo mount -t btrfs -o recovery,ro /dev/sdaa /mnt/roms03 mount: wrong fs type, bad option, bad superblock on /dev/sdaa, missing codepage or helper program, or other error In some cases useful info is found in syslog - try dmesg | tail or so$ dmesg -T|tail [Mon May 4 08:35:08 2015] BTRFS info (device sdz): enabling auto recovery [Mon May 4 08:35:08 2015] BTRFS info (device sdz): disk space caching is enabled [Mon May 4 08:35:08 2015] BTRFS: has skinny extents [Mon May 4 08:35:08 2015] BTRFS: failed to read chunk tree on sdz [Mon May 4 08:35:08 2015] BTRFS: open_ctree failed
Quoted 2 lines
What could I try to see if I can mount this pool and gain access to the data?
A disk is missing, in this case you should use the "degraded" mount option:
mount -o degraded /dev/sdaa /mnt/roms03
Quoted 10 lines
While I have a backup of the data, next time I may not, and I am trying to learn how to go about.
--
To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Signature · 2 lines
gpg @keyserver.linux.it: Goffredo Baroncelli <kreijackATinwind.it> Key fingerprint BBF5 1610 0B64 DAC6 5F7D 17B2 0EDA 9B37 8B82 E0B5
Quoted 3 lines · Goffredo Baroncelli
A disk is missing, in this case you should use the "degraded" mount option:
mount -o degraded
/dev/sdaa/mnt/roms03
Goffredo - Thanks for responding - I tried that, but to no avail:
$ sudo mount -o degraded /dev/sdaa /mnt/roms03
mount: wrong fs type, bad option, bad superblock on /dev/sdaa,
missing codepage or helper program, or other error
In some cases useful info is found in syslog - try
dmesg | tail or so$ dmesg -T|tail [Mon May 4 14:33:17 2015] BTRFS info (device sdaa): allowing degraded mounts [Mon May 4 14:33:17 2015] BTRFS info (device sdaa): disk space caching is enabled [Mon May 4 14:33:17 2015] BTRFS: has skinny extents [Mon May 4 14:33:17 2015] BTRFS: bdev (null) errs: wr 3, rd 28773, flush 2, corrupt 0, gen 0 [Mon May 4 14:33:22 2015] BTRFS (device sdaa): bad tree block start 8714499618262386624 1585233920 [Mon May 4 14:33:22 2015] BTRFS (device sdaa): bad tree block start 8714499618262386624 1585233920 [Mon May 4 14:33:22 2015] BTRFS (device sdaa): bad tree block start 8714499618262386624 1585233920 [Mon May 4 14:33:22 2015] BTRFS (device sdaa): bad tree block start 8714499618262386624 1585233920 [Mon May 4 14:33:22 2015] BTRFS: Failed to read block groups: -5 [Mon May 4 14:33:22 2015] BTRFS: open_ctree failed
Quoted 7 lines · TheJay
$ sudo btrfs fi show
Label: 'roms03' uuid: b0025417-4045-4c63-a432-0625b7cc41ea
Total devices 4 FS bytes used 2.67TiB
devid 1 size 1.36TiB used 1.36TiB path /dev/sdz
devid 3 size 1.36TiB used 1.36TiB path /dev/sdaa
devid 4 size 1.36TiB used 1.36TiB path /dev/sdab
*** Some devices missingHow many devices are missing?
Quoted 1 line
[Mon May 4 08:35:08 2015] BTRFS: failed to read chunk tree on sdz
That's not good. What do you get for 'btrfs check" (without --repair)?
Signature · 1 line
Chris Murphy
Quoted 1 line · TheJay
[Mon May 4 14:33:17 2015] BTRFS: bdev (null) errs: wr 3, rd 28773, flush 2, corrupt 0, gen 0
So there might be more than one thing going wrong and they're colliding to make a worse problem. You've got three write and 2 flush errors, and many thousands of read errors (probably due to missing devices).
It might be worth trying -o degraded,recovery because recovery can't work with devices missing, and degraded alone won't run the recovery code.
Signature · 1 line
Chris Murphy
Quoted 4 lines · Chris Murphy
Quoted 1 line · TheJay
[Mon May 4 14:33:17 2015] BTRFS: bdev (null) errs: wr 3, rd 28773, flush 2, corrupt 0, gen 0
Quoted 12 lines
So there might be more than one thing going wrong and they're colliding to make a worse problem. You've got three write and 2 flush errors, and many thousands of read errors (probably due to missing devices).
It might be worth trying -o degraded,recovery because recovery can't work with devices missing, and degraded alone won't run the recovery code.
Signature · 1 line
Chris Murphy
$ mount -o degraded,recovery /dev/sdz /mnt/roms03
mount: wrong fs type, bad option, bad superblock on /dev/sdy,
missing codepage or helper program, or other error
In some cases useful info is found in syslog - try
dmesg | tail or so$ dmesg -T|tail [Tue May 5 00:26:01 2015] BTRFS info (device sdaa): enabling auto recovery [Tue May 5 00:26:01 2015] BTRFS info (device sdaa): disk space caching is enabled [Tue May 5 00:26:01 2015] BTRFS: has skinny extents [Tue May 5 00:26:01 2015] BTRFS: bdev (null) errs: wr 3, rd 28773, flush 2, corrupt 0, gen 0 [Tue May 5 00:26:05 2015] BTRFS (device sdaa): bad tree block start 8714499618262386624 1585233920 [Tue May 5 00:26:05 2015] BTRFS (device sdaa): bad tree block start 8714499618262386624 1585233920 [Tue May 5 00:26:05 2015] BTRFS (device sdaa): bad tree block start 8714499618262386624 1585233920 [Tue May 5 00:26:05 2015] BTRFS (device sdaa): bad tree block start 8714499618262386624 1585233920 [Tue May 5 00:26:05 2015] BTRFS: Failed to read block groups: -5 [Tue May 5 00:26:06 2015] BTRFS: open_ctree failed
Quoted 9 lines · Chris Murphy
Quoted 7 lines · TheJay
$ sudo btrfs fi show Label: 'roms03' uuid: b0025417-4045-4c63-a432-0625b7cc41ea Total devices 4 FS bytes used 2.67TiB devid 1 size 1.36TiB used 1.36TiB path /dev/sdz devid 3 size 1.36TiB used 1.36TiB path /dev/sdaa devid 4 size 1.36TiB used 1.36TiB path /dev/sdab *** Some devices missing
Quoted 8 lines
How many devices are missing?
Quoted 1 line
[Mon May 4 08:35:08 2015] BTRFS: failed to read chunk tree on sdzThat's not good. What do you get for 'btrfs check" (without --repair)?
Signature · 1 line
Chris Murphy
Appriciate the response Chris
Quoted 1 line
How many devices are missing?
One (1) of the 4 devices is missing - "device 2".
Quoted 1 line
What do you get for 'btrfs check" (without --repair)?
$ btrfs check /dev/sdaa warning, device 2 is missing warning devid 2 not found already checksum verify failed on 21200896 found 44715E95 wanted A092E323 checksum verify failed on 21200896 found 91AC994F wanted 987F5E0F checksum verify failed on 21200896 found 44715E95 wanted A092E323 bytenr mismatch, want=21200896, have=65536 Couldn't read chunk tree Couldn't open file system
TheJay posted on Mon, 04 May 2015 15:44:35 +0000 as excerpted:
Quoted 5 lines
What could I try to see if I can mount this pool and gain access to the data?
While I have a backup of the data, next time I may not, and I am trying to learn how to go about.
If you can't get it to mount based on the other subthreads, and you have sufficient space on an existing/working filesystem to recover the files to, you can try btrfs restore.
I wrote up a longer reply covering restore in another recent thread, "Help on broken filesystem", OP by Ermanno Baschiera, which should be in the archives... yes...
http://permalink.gmane.org/gmane.comp.file-systems.btrfs/44765
That in turn refers to the (outdated) restore writeup on the wiki.
Since then, I had to use it again myself, updating my year-old personal experience. Among other things, btrfs-progs v4.0 has a new metadata restore option, which should restore ownership/perms/dates as well as the file data. There's a patch to restore symlinks too, but it apparently didn't make it into 4.0, so you'll have to try the integration branch or apply it manually after finding it on the list. The looping too many times point apparently doesn't apply any more, at least on a full run, tho it still cuts short if you use the dry-run option. Additionally, the dry-run option gave me some metadata restoration errors that a full write- files run didn't give me, so dry-run ends up being rather more pessimistic about what can be restored than what it actually restores.
If you're lucky, restore will "just work". If not, you can try feeding it roots you found using btrfs-find-root, as detailed in the above post. On my recent experience I was lucky and it worked without that, so I didn't get to update my personal experience knowledge in that regard.
You did say you have a backup (good admin! =:^) this time, but wanted to practice in case you weren't so lucky next time. Practice is good, and practicing restore when you don't /have/ to depend on it as you have a current backup is even better, but do keep in mind the admin's backup rule I mention in the other post.
As it happens, I had a backup I could have used in my recent restore experience case as well, but it wasn't as current as I'd have liked. I had knowingly taken that risk and would have settled for the old backup if I had to, but restore gave me the very pleasant (under the circumstances) choice of either the more current copies from btrfs restore but having to redo the symlinks manually, or using the older backup. It's actually very nice having that choice as it takes all the pressure away of worrying about fat-fingering the one chance you'd otherwise have left! =:^)
Plus, while restore "just worked" for me this time, if it hadn't and I had to do the find-root thing, I would have had the luxury of simply saying OK, too much hassle, I'll just use the older backups and go from there. I'd have probably still tried the find-root thing, because they /were/ more current and as you note having the experience is good, but again, with the backups if I had to use 'em, the pressure would have been off, and that in itself is valuable. =:^)
Signature · 3 lines
Duncan - List replies preferred. No HTML msgs. "Every nonfree program has a lord, a master -- and if you use the program, he is your master." Richard Stallman
Quoted 12 lines · Duncan
Since then, I had to use it again myself, updating my year-old personal experience. Among other things, btrfs-progs v4.0 has a new metadata restore option, which should restore ownership/perms/dates as well as the file data. There's a patch to restore symlinks too, but it apparently didn't make it into 4.0, so you'll have to try the integration branch or apply it manually after finding it on the list. The looping too many times point apparently doesn't apply any more, at least on a full run, tho it still cuts short if you use the dry-run option. Additionally, the dry-run option gave me some metadata restoration errors that a full write- files run didn't give me, so dry-run ends up being rather more pessimistic about what can be restored than what it actually restores.
Quoted 4 lines
If you're lucky, restore will "just work". If not, you can try feeding it roots you found using btrfs-find-root, as detailed in the above post. On my recent experience I was lucky and it worked without that, so I didn't get to update my personal experience knowledge in that regard.
Duncan,
Many thanks for taking the time to look at my case, and to make the effort of writing such an elaborate response - much appreciated. I understand the direction I should be taking, and by just reading your response have learned quite a bit already.
Unfortunately I got stranded right at the get-go, with the btrfs-show super command not working for me. Let me share a couple of outputs, and hopefully you or others can point me where to go from here. As a side-note, I did update to btrfs-progs 4.0 from 3.19.2 as suggested.
$ btrfs --version btrfs-progs v4.0
$ sudo uname -a Linux thejay-srv03 4.0.0-040000-generic #201504121935 SMP Sun Apr 12 23:36:33 UTC 2015 x86_64 x86_64 x86_64 GNU/Linux
Just for clarity - this is a btrfsraid6 pool.
$ sudo btrfs fi show /dev/sdy warning, device 2 is missing warning devid 2 not found already checksum verify failed on 21200896 found 44715E95 wanted A092E323 checksum verify failed on 21200896 found 91AC994F wanted 987F5E0F checksum verify failed on 21200896 found 44715E95 wanted A092E323 bytenr mismatch, want=21200896, have=65536 Couldn't read chunk tree Label: 'roms03' uuid: b0025417-4045-4c63-a432-0625b7cc41ea Total devices 4 FS bytes used 2.67TiB devid 1 size 1.36TiB used 1.36TiB path /dev/sdy devid 3 size 1.36TiB used 1.36TiB path /dev/sdz devid 4 size 1.36TiB used 1.36TiB path /dev/sdaa *** Some devices missing
btrfs-progs v4.0
$ sudo btrfs-find-root /dev/sdy warning, device 2 is missing warning devid 2 not found already Couldn't read chunk tree Open ctree failed
(above output is the same for the other 2 drives sdz and sdaa)
$ sudo btrfs-show-super /dev/sdy superblock: bytenr=65536, device=/dev/sdy --------------------------------------------------------- csum 0x8c55bcfe [match] bytenr 65536 flags 0x1 magic _BHRfS_M [match] fsid b0025417-4045-4c63-a432-0625b7cc41ea label roms03 generation 17310 root 1622245376 sys_array_size 290 chunk_root_generation 16372 root_level 1 chunk_root 20971520 chunk_root_level 1 log_root 0 log_root_transid 0 log_root_level 0 total_bytes 6001207640064 bytes_used 2937720725504 sectorsize 4096 nodesize 16384 leafsize 16384 stripesize 4096 root_dir 6 num_devices 4 compat_flags 0x0 compat_ro_flags 0x0 incompat_flags 0x1e1 ( MIXED_BACKREF | BIG_METADATA | EXTENDED_IREF | RAID56 | SKINNY_METADATA ) csum_type 0 csum_size 4 cache_generation 17310 uuid_tree_generation 17310 dev_item.uuid f39d7af1-1eec-4f99-8353-4c70371e1942 dev_item.fsid b0025417-4045-4c63-a432-0625b7cc41ea [match] dev_item.type 0 dev_item.total_bytes 1500301910016 dev_item.bytes_used 1500301885440 dev_item.io_align 4096 dev_item.io_width 4096 dev_item.sector_size 4096 dev_item.devid 1 dev_item.dev_group 0 dev_item.seek_speed 0 dev_item.bandwidth 0 dev_item.generation 0
----
$ sudo btrfs-show-super /dev/sdz superblock: bytenr=65536, device=/dev/sdz --------------------------------------------------------- csum 0xb48f16eb [match] bytenr 65536 flags 0x1 magic _BHRfS_M [match] fsid b0025417-4045-4c63-a432-0625b7cc41ea label roms03 generation 17310 root 1622245376 sys_array_size 290 chunk_root_generation 16372 root_level 1 chunk_root 20971520 chunk_root_level 1 log_root 0 log_root_transid 0 log_root_level 0 total_bytes 6001207640064 bytes_used 2937720725504 sectorsize 4096 nodesize 16384 leafsize 16384 stripesize 4096 root_dir 6 num_devices 4 compat_flags 0x0 compat_ro_flags 0x0 incompat_flags 0x1e1 ( MIXED_BACKREF | BIG_METADATA | EXTENDED_IREF | RAID56 | SKINNY_METADATA ) csum_type 0 csum_size 4 cache_generation 17310 uuid_tree_generation 17310 dev_item.uuid 6560226f-a966-4699-8a9e-e7377d436cc6 dev_item.fsid b0025417-4045-4c63-a432-0625b7cc41ea [match] dev_item.type 0 dev_item.total_bytes 1500301910016 dev_item.bytes_used 1500300836864 dev_item.io_align 4096 dev_item.io_width 4096 dev_item.sector_size 4096 dev_item.devid 3 dev_item.dev_group 0 dev_item.seek_speed 0 dev_item.bandwidth 0 dev_item.generation 0
----
$ sudo btrfs-show-super /dev/sdaa superblock: bytenr=65536, device=/dev/sdaa --------------------------------------------------------- csum 0xf3cbbf1f [match] bytenr 65536 flags 0x1 magic _BHRfS_M [match] fsid b0025417-4045-4c63-a432-0625b7cc41ea label roms03 generation 17310 root 1622245376 sys_array_size 290 chunk_root_generation 16372 root_level 1 chunk_root 20971520 chunk_root_level 1 log_root 0 log_root_transid 0 log_root_level 0 total_bytes 6001207640064 bytes_used 2937720725504 sectorsize 4096 nodesize 16384 leafsize 16384 stripesize 4096 root_dir 6 num_devices 4 compat_flags 0x0 compat_ro_flags 0x0 incompat_flags 0x1e1 ( MIXED_BACKREF | BIG_METADATA | EXTENDED_IREF | RAID56 | SKINNY_METADATA ) csum_type 0 csum_size 4 cache_generation 17310 uuid_tree_generation 17310 dev_item.uuid 3c026bb0-dcf0-45da-8c90-cb668323180d dev_item.fsid b0025417-4045-4c63-a432-0625b7cc41ea [match] dev_item.type 0 dev_item.total_bytes 1500301910016 dev_item.bytes_used 1500300836864 dev_item.io_align 4096 dev_item.io_width 4096 dev_item.sector_size 4096 dev_item.devid 4 dev_item.dev_group 0 dev_item.seek_speed 0 dev_item.bandwidth 0 dev_item.generation 0
Quoted 12 lines · Duncan
Since then, I had to use it again myself, updating my year-old personal experience. Among other things, btrfs-progs v4.0 has a new metadata restore option, which should restore ownership/perms/dates as well as the file data. There's a patch to restore symlinks too, but it apparently didn't make it into 4.0, so you'll have to try the integration branch or apply it manually after finding it on the list. The looping too many times point apparently doesn't apply any more, at least on a full run, tho it still cuts short if you use the dry-run option. Additionally, the dry-run option gave me some metadata restoration errors that a full write- files run didn't give me, so dry-run ends up being rather more pessimistic about what can be restored than what it actually restores.
Please ignore the last post - had 2 typos in it that could confuse my problem as to where I now got stuck (btrfs-show-super instead of btrfs-find-root, btrfs-progs version)
Duncan,
Many thanks for taking the time to look at my case, and to make the effort of writing such an elaborate response - much appreciated. I understand the direction I should be taking, and by just reading your response have learned quite a bit already.
Unfortunately I got stranded right at the get-go, with the btrfs-find-root command not working for me. Let me share a couple of outputs, and hopefully you or others can point me where to go from here. As a side-note, I did update to btrfs-progs 4.0 from 3.19.1 as suggested.
$ btrfs --version btrfs-progs v4.0
$ sudo uname -a Linux thejay-srv03 4.0.0-040000-generic #201504121935 SMP Sun Apr 12 23:36:33 UTC 2015 x86_64 x86_64 x86_64 GNU/Linux
Just for clarity - this is a btrfsraid6 pool.
$ sudo btrfs fi show /dev/sdy warning, device 2 is missing warning devid 2 not found already checksum verify failed on 21200896 found 44715E95 wanted A092E323 checksum verify failed on 21200896 found 91AC994F wanted 987F5E0F checksum verify failed on 21200896 found 44715E95 wanted A092E323 bytenr mismatch, want=21200896, have=65536 Couldn't read chunk tree Label: 'roms03' uuid: b0025417-4045-4c63-a432-0625b7cc41ea Total devices 4 FS bytes used 2.67TiB devid 1 size 1.36TiB used 1.36TiB path /dev/sdy devid 3 size 1.36TiB used 1.36TiB path /dev/sdz devid 4 size 1.36TiB used 1.36TiB path /dev/sdaa *** Some devices missing
btrfs-progs v4.0
$ sudo btrfs-find-root /dev/sdy warning, device 2 is missing warning devid 2 not found already Couldn't read chunk tree Open ctree failed
(above output is the same for the other 2 drives sdz and sdaa)
$ sudo btrfs-show-super /dev/sdy superblock: bytenr=65536, device=/dev/sdy --------------------------------------------------------- csum 0x8c55bcfe [match] bytenr 65536 flags 0x1 magic _BHRfS_M [match] fsid b0025417-4045-4c63-a432-0625b7cc41ea label roms03 generation 17310 root 1622245376 sys_array_size 290 chunk_root_generation 16372 root_level 1 chunk_root 20971520 chunk_root_level 1 log_root 0 log_root_transid 0 log_root_level 0 total_bytes 6001207640064 bytes_used 2937720725504 sectorsize 4096 nodesize 16384 leafsize 16384 stripesize 4096 root_dir 6 num_devices 4 compat_flags 0x0 compat_ro_flags 0x0 incompat_flags 0x1e1 ( MIXED_BACKREF | BIG_METADATA | EXTENDED_IREF | RAID56 | SKINNY_METADATA ) csum_type 0 csum_size 4 cache_generation 17310 uuid_tree_generation 17310 dev_item.uuid f39d7af1-1eec-4f99-8353-4c70371e1942 dev_item.fsid b0025417-4045-4c63-a432-0625b7cc41ea [match] dev_item.type 0 dev_item.total_bytes 1500301910016 dev_item.bytes_used 1500301885440 dev_item.io_align 4096 dev_item.io_width 4096 dev_item.sector_size 4096 dev_item.devid 1 dev_item.dev_group 0 dev_item.seek_speed 0 dev_item.bandwidth 0 dev_item.generation 0
----
$ sudo btrfs-show-super /dev/sdz superblock: bytenr=65536, device=/dev/sdz --------------------------------------------------------- csum 0xb48f16eb [match] bytenr 65536 flags 0x1 magic _BHRfS_M [match] fsid b0025417-4045-4c63-a432-0625b7cc41ea label roms03 generation 17310 root 1622245376 sys_array_size 290 chunk_root_generation 16372 root_level 1 chunk_root 20971520 chunk_root_level 1 log_root 0 log_root_transid 0 log_root_level 0 total_bytes 6001207640064 bytes_used 2937720725504 sectorsize 4096 nodesize 16384 leafsize 16384 stripesize 4096 root_dir 6 num_devices 4 compat_flags 0x0 compat_ro_flags 0x0 incompat_flags 0x1e1 ( MIXED_BACKREF | BIG_METADATA | EXTENDED_IREF | RAID56 | SKINNY_METADATA ) csum_type 0 csum_size 4 cache_generation 17310 uuid_tree_generation 17310 dev_item.uuid 6560226f-a966-4699-8a9e-e7377d436cc6 dev_item.fsid b0025417-4045-4c63-a432-0625b7cc41ea [match] dev_item.type 0 dev_item.total_bytes 1500301910016 dev_item.bytes_used 1500300836864 dev_item.io_align 4096 dev_item.io_width 4096 dev_item.sector_size 4096 dev_item.devid 3 dev_item.dev_group 0 dev_item.seek_speed 0 dev_item.bandwidth 0 dev_item.generation 0
----
$ sudo btrfs-show-super /dev/sdaa superblock: bytenr=65536, device=/dev/sdaa --------------------------------------------------------- csum 0xf3cbbf1f [match] bytenr 65536 flags 0x1 magic _BHRfS_M [match] fsid b0025417-4045-4c63-a432-0625b7cc41ea label roms03 generation 17310 root 1622245376 sys_array_size 290 chunk_root_generation 16372 root_level 1 chunk_root 20971520 chunk_root_level 1 log_root 0 log_root_transid 0 log_root_level 0 total_bytes 6001207640064 bytes_used 2937720725504 sectorsize 4096 nodesize 16384 leafsize 16384 stripesize 4096 root_dir 6 num_devices 4 compat_flags 0x0 compat_ro_flags 0x0 incompat_flags 0x1e1 ( MIXED_BACKREF | BIG_METADATA | EXTENDED_IREF | RAID56 | SKINNY_METADATA ) csum_type 0 csum_size 4 cache_generation 17310 uuid_tree_generation 17310 dev_item.uuid 3c026bb0-dcf0-45da-8c90-cb668323180d dev_item.fsid b0025417-4045-4c63-a432-0625b7cc41ea [match] dev_item.type 0 dev_item.total_bytes 1500301910016 dev_item.bytes_used 1500300836864 dev_item.io_align 4096 dev_item.io_width 4096 dev_item.sector_size 4096 dev_item.devid 4 dev_item.dev_group 0 dev_item.seek_speed 0 dev_item.bandwidth 0 dev_item.generation 0