Got this:
[root@rockstor ~]# btrfs-show-super -f /dev/sdg
superblock: bytenr=65536, device=/dev/sdg
---------------------------------------------------------
csum 0x793978ef [match]
bytenr 65536
flags 0x1
( WRITTEN )
magic _BHRfS_M [match]
fsid e8c92d93-fac3-4f83-b3aa-31cb92caafd9
label mainNAS
generation 25209
root 8640557629440
sys_array_size 225
chunk_root_generation 25196
root_level 1
chunk_root 12060305932288
chunk_root_level 1
log_root 0
log_root_transid 0
log_root_level 0
total_bytes 15002964910080
bytes_used 5973553180672
sectorsize 4096
nodesize 16384
leafsize 16384
stripesize 4096
root_dir 6
num_devices 5
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 25209
uuid_tree_generation 25209
dev_item.uuid 286474b1-210d-4db1-b97f-ff07116bf2f9
dev_item.fsid e8c92d93-fac3-4f83-b3aa-31cb92caafd9 [match]
dev_item.type 0
dev_item.total_bytes 3000592982016
dev_item.bytes_used 1497618186240
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
sys_chunk_array[2048]:
item 0 key (FIRST_CHUNK_TREE CHUNK_ITEM 12060305915904)
chunk length 67108864 owner 2 stripe_len 65536
type SYSTEM|RAID5 num_stripes 5
stripe 0 devid 4 offset 1074790400
stripe 1 devid 5 offset 1074790400
stripe 2 devid 1 offset 1371537408
stripe 3 devid 3 offset 1351614464
stripe 4 devid 2 offset 1351614464
backup_roots[4]:
backup 0:
backup_tree_root: 8640557629440 gen: 25209 level: 1
backup_chunk_root: 12060305932288 gen: 25196 level: 1
backup_extent_root: 8640865320960 gen: 25209 level: 2
backup_fs_root: 6680017420288 gen: 25128 level: 0
backup_dev_root: 7742127030272 gen: 25196 level: 1
backup_csum_root: 8640864288768 gen: 25209 level: 3
backup_total_bytes: 15002964910080
backup_bytes_used: 5973553180672
backup_num_devices: 5
backup 1:
backup_tree_root: 7742772379648 gen: 25206 level: 1
backup_chunk_root: 12060305932288 gen: 25196 level: 1
backup_extent_root: 7742740856832 gen: 25206 level: 2
backup_fs_root: 6680017420288 gen: 25128 level: 0
backup_dev_root: 7742127030272 gen: 25196 level: 1
backup_csum_root: 7742662393856 gen: 25206 level: 3
backup_total_bytes: 15002964910080
backup_bytes_used: 5972952920064
backup_num_devices: 5
backup 2:
backup_tree_root: 7742732894208 gen: 25207 level: 1
backup_chunk_root: 12060305932288 gen: 25196 level: 1
backup_extent_root: 7742674255872 gen: 25207 level: 2
backup_fs_root: 6680017420288 gen: 25128 level: 0
backup_dev_root: 7742127030272 gen: 25196 level: 1
backup_csum_root: 7742665457664 gen: 25207 level: 3
backup_total_bytes: 15002964910080
backup_bytes_used: 5973141712896
backup_num_devices: 5
backup 3:
backup_tree_root: 8640836403200 gen: 25208 level: 1
backup_chunk_root: 12060305932288 gen: 25196 level: 1
backup_extent_root: 8640865320960 gen: 25209 level: 2
backup_fs_root: 6680017420288 gen: 25128 level: 0
backup_dev_root: 7742127030272 gen: 25196 level: 1
backup_csum_root: 8640864288768 gen: 25209 level: 3
backup_total_bytes: 15002964910080
backup_bytes_used: 5973372186624
backup_num_devices: 5
[root@rockstor ~]#
Thanks,
Scotty Edmonds
Scotty@xxxxxxxxxxxxxxxxx
________________________________________
From: Qu Wenruo <quwenruo@xxxxxxxxxxxxxx>
Sent: November-12-15 11:00 PM
To: Scotty Edmonds; Hugo Mills; Donald Pearson
Cc: Btrfs BTRFS
Subject: Re: BTRFS Error - Rockstor
Although I submitted a patch, that won't work for you.
As I found that your whole chunk tree is corrupted, so I'll need to add
a new mode for you to handle such case, which will be much time
consuming than the patch I submitted...
But your superblock should has some glue if we are in good luck.
Would you please paste the output of 'btrfs-show-super -f <device>'?
If we are in good luck, it has something like:
------
backup 0:
backup_tree_root: 30932992 gen: 10 level: 0
backup_chunk_root: 20971520 gen: 9 level: 0
backup_extent_root: 30916608 gen: 10 level: 0
backup_fs_root: 30982144 gen: 10 level: 0
backup_dev_root: 29458432 gen: 8 level: 0
backup_csum_root: 30949376 gen: 10 level: 1
backup_total_bytes: 1073741824
backup_bytes_used: 949682176
backup_num_devices: 1
backup 1:
backup_tree_root: 30998528 gen: 11 level: 0
backup_chunk_root: 20971520 gen: 8 level: 0
backup_extent_root: 31014912 gen: 11 level: 0
backup_fs_root: 30982144 gen: 10 level: 0
backup_dev_root: 29458432 gen: 8 level: 0
backup_csum_root: 30949376 gen: 10 level: 1
backup_total_bytes: 1073741824
backup_bytes_used: 949682176
backup_num_devices: 1
------
And if the back_chunk_root's gen is smaller than
'chunk_root_generation', you're in good luck and can use that chunk root
to give it a try.
Thanks,
Qu
Scotty Edmonds wrote on 2015/11/13 02:23 +0000:
> yes, no problem. I had it powered off as I'm moving the system to a proper chassis and won't have it for another two weeks.
>
> Thanks,
>
> Scotty Edmonds
> Scotty@xxxxxxxxxxxxxxxxx
>
> ________________________________________
> From: Qu Wenruo <quwenruo@xxxxxxxxxxxxxx>
> Sent: November-12-15 10:21 PM
> To: Scotty Edmonds; Hugo Mills; Donald Pearson
> Cc: Btrfs BTRFS
> Subject: Re: BTRFS Error - Rockstor
>
> Chunk root seems corrupted.
> But that's not a really huge problem, tree root corruption happens, and
> thanks to the full CoW of btrfs metadata, we will always be able to find
> a old version one.
>
> I'd like to do a full disk scan for any earlier version chunk root, but
> I found that btrfs-find-root doesn't support search for chunk root.
> (Hey, who is the bad ass wrote btrfs-find-root and made chunk root
> search unsupported?! Oh, that's myself)
>
> If you can wait, I'll add chunk root search support for you in recent
> days, and then hopes we can find something helpful.
>
> Thanks,
> Qu
>
> Scotty Edmonds wrote on 2015/11/13 01:46 +0000:
>> Thanks for the help, I got the same error on all variants.
>>
>> [root@rockstor ~]# btrfs check --readonly -s 0 /dev/sdh
>> using SB copy 0, bytenr 65536
>> checksum verify failed on 12060305965056 found 779CCA23 wanted A746C37A
>> checksum verify failed on 12060305965056 found 779CCA23 wanted A746C37A
>> checksum verify failed on 12060305965056 found 1727A198 wanted 231E1577
>> checksum verify failed on 12060305965056 found 1727A198 wanted 231E1577
>> bytenr mismatch, want=12060305965056, have=13820656527619066643
>> Couldn't read chunk tree
>> Couldn't open file system
>> [root@rockstor ~]#
>>
>>
>> Thanks,
>>
>> Scotty Edmonds
>> Scotty@xxxxxxxxxxxxxxxxx
>>
>> ________________________________________
>> From: Hugo Mills <hugo@xxxxxxxxxxxxx>
>> Sent: November-12-15 6:57 PM
>> To: Donald Pearson
>> Cc: Scotty Edmonds; Btrfs BTRFS
>> Subject: Re: BTRFS Error - Rockstor
>>
>> On IRC earlier, I asked for the btrfs-debug-tree output of the
>> broken tree block (1205030...etc). Since it's also failing, that would
>> kind of indicate that this is pretty badly broken for some reason.
>>
>> It doesn't quite feel like a broken disk to me, but I'm not sure
>> what _has_ happened. Looks like something has stomped on a piece of
>> metadata fairly high up in the data structures.
>>
>> It probably won't show anything different, but could you do
>>
>> $ btrfs check --readonly -s $N /dev/$D
>>
>> for values of $N from 0 to 3, and for all the devices $D? I'm
>> expecting to see the same errors (except for -s3, which is probably
>> out of range), but if by any chance you get something different, that
>> may give us a way into recovery.
>>
>> Hugo.
>>
>> On Thu, Nov 12, 2015 at 04:41:58PM -0600, Donald Pearson wrote:
>>> On Thu, Nov 12, 2015 at 4:24 PM, Scotty Edmonds
>>> <scotty@xxxxxxxxxxxxxxxxx> wrote:
>>>> Not exactly sure what to look for in dmesg.. If it is a disk fail shouldn't I just be able to remove the disk as it's RAID5?
>>>>
>>>
>>> Yes theoretically.
>>>
>>>
>>>> [ 20.323997] BTRFS: device label seagate3x2tb devid 2 transid 2315 /dev/sdc
>>>> [ 20.324387] BTRFS: device label seagate3x2tb devid 1 transid 2315 /dev/sda
>>>> [ 20.324601] BTRFS: device label seagate3x2tb devid 3 transid 2315 /dev/sdd
>>>> [ 20.324698] BTRFS: device label mainNAS devid 1 transid 25209 /dev/sdg
>>>> [ 20.324794] BTRFS: device label mainNAS devid 2 transid 25209 /dev/sdf
>>>> [ 20.324938] BTRFS: device label mainNAS devid 5 transid 25209 /dev/sde
>>>> [ 20.325124] BTRFS: device label mainNAS devid 4 transid 25209 /dev/sdb
>>>> [ 20.325256] BTRFS: device label mainNAS devid 3 transid 25209 /dev/sdh
>>>> [ 105.285746] BTRFS info (device sdh): disk space caching is enabled
>>>> [ 105.285753] BTRFS: has skinny extents
>>>> [ 105.756545] BTRFS (device sdh): bad tree block start 13820666663704185619 12060305965056
>>>> [ 105.758877] BTRFS (device sdh): bad tree block start 13820666663704185619 12060305965056
>>>> [ 105.759154] BTRFS (device sdh): bad tree block start 13820666663704185619 12060305965056
>>>> [ 105.759340] BTRFS (device sdh): bad tree block start 13820666663704185619 12060305965056
>>>> [ 105.759417] BTRFS: failed to read chunk tree on sdh
>>>> [ 105.774774] BTRFS: open_ctree failed
>>>> [ 127.736060] BTRFS info (device sdd): disk space caching is enabled
>>>> [ 127.736066] BTRFS: has skinny extents
>>>> [ 141.887422] BTRFS info (device sdh): disk space caching is enabled
>>>> [ 141.887428] BTRFS: has skinny extents
>>>> [ 141.899666] BTRFS (device sdh): bad tree block start 13820666663704185619 12060305965056
>>>> [ 141.902385] BTRFS (device sdh): bad tree block start 13820666663704185619 12060305965056
>>>> [ 141.902639] BTRFS (device sdh): bad tree block start 13820666663704185619 12060305965056
>>>> [ 141.902795] BTRFS (device sdh): bad tree block start 13820666663704185619 12060305965056
>>>> [ 141.902870] BTRFS: failed to read chunk tree on sdh
>>>> [ 141.915337] BTRFS: open_ctree failed
>>>> [17748.031552] BTRFS info (device sdh): disk space caching is enabled
>>>> [17748.031559] BTRFS: has skinny extents
>>>> [17748.072339] BTRFS (device sdh): bad tree block start 13820666663704185619 12060305965056
>>>> [17748.077023] BTRFS (device sdh): bad tree block start 13820666663704185619 12060305965056
>>>> [17748.077350] BTRFS (device sdh): bad tree block start 13820666663704185619 12060305965056
>>>> [17748.077511] BTRFS (device sdh): bad tree block start 13820666663704185619 12060305965056
>>>> [17748.077587] BTRFS: failed to read chunk tree on sdh
>>>> [17748.088908] BTRFS: open_ctree failed
>>>> [17800.758291] BTRFS info (device sdh): disk space caching is enabled
>>>> [17800.758298] BTRFS: has skinny extents
>>>> [17800.765770] BTRFS (device sdh): bad tree block start 13820666663704185619 12060305965056
>>>> [17800.768816] BTRFS (device sdh): bad tree block start 13820666663704185619 12060305965056
>>>> [17800.769054] BTRFS (device sdh): bad tree block start 13820666663704185619 12060305965056
>>>> [17800.769192] BTRFS (device sdh): bad tree block start 13820666663704185619 12060305965056
>>>> [17800.769264] BTRFS: failed to read chunk tree on sdh
>>>> [17800.784937] BTRFS: open_ctree failed
>>>> [root@rockstor ~]#
>>>>
>>>> and then I get this:
>>>>
>>>> [root@rockstor ~]# btrfs-debug-tree -b 12060305965056 /dev/sdh
>>>> checksum verify failed on 12060305965056 found 779CCA23 wanted A746C37A
>>>> checksum verify failed on 12060305965056 found 779CCA23 wanted A746C37A
>>>> checksum verify failed on 12060305965056 found 1727A198 wanted 231E1577
>>>> checksum verify failed on 12060305965056 found 1727A198 wanted 231E1577
>>>> bytenr mismatch, want=12060305965056, have=13820656527619066643
>>>> Couldn't read chunk tree
>>>> unable to open /dev/sdh
>>>> [root@rockstor ~]#
>>>>
>>>> Thanks,
>>>>
>>>> Scotty Edmonds
>>>> Scotty@xxxxxxxxxxxxxxxxx
>>>
>>> I think we need to see what some of the more experienced users think
>>> on this one. But you can try removing sdh and seeing if you can mount
>>> it *read only* and degraded. Just make sure whatever you do and play
>>> with is done read only. Don't try any fixes or repairs with the tools
>>> unless told to do so by someone who really knows what they're talking
>>> about.
>>>
>>>>
>>>> ________________________________________
>>>> From: Donald Pearson <donaldwhpearson@xxxxxxxxx>
>>>> Sent: November-12-15 6:19 PM
>>>> To: Scotty Edmonds; Btrfs BTRFS
>>>> Subject: Re: BTRFS Error - Rockstor
>>>>
>>>> Anything interesting in dmesg?
>>>>
>>>> That looks similar to the kind of problems I had when I had a disk fail.
>>>>
>>>> On Thu, Nov 12, 2015 at 4:08 PM, Scotty Edmonds
>>>> <scotty@xxxxxxxxxxxxxxxxx> wrote:
>>>>> I get this:
>>>>>
>>>>> [root@rockstor ~]# btrfs check /dev/sdd
>>>>> checksum verify failed on 12060305965056 found 779CCA23 wanted A746C37A
>>>>> checksum verify failed on 12060305965056 found 779CCA23 wanted A746C37A
>>>>> checksum verify failed on 12060305965056 found 1727A198 wanted 231E1577
>>>>> checksum verify failed on 12060305965056 found 1727A198 wanted 231E1577
>>>>> bytenr mismatch, want=12060305965056, have=13820656527619066643
>>>>> Couldn't read chunk tree
>>>>> Couldn't open file system
>>>>> [root@rockstor ~]#
>>>>>
>>>>> Thanks,
>>>>>
>>>>> Scotty Edmonds
>>>>> Scotty@xxxxxxxxxxxxxxxxx
>>>>>
>>>>> ________________________________________
>>>>> From: Donald Pearson <donaldwhpearson@xxxxxxxxx>
>>>>> Sent: November-12-15 2:55 PM
>>>>> To: Scotty Edmonds
>>>>> Cc: linux-btrfs@xxxxxxxxxxxxxxx
>>>>> Subject: Re: BTRFS Error - Rockstor
>>>>>
>>>>> What does btrfs check without any repair options report?
>>>>>
>>>>> btrfs check /dev/sdd
>>>>>
>>>>> On Thu, Nov 12, 2015 at 12:48 PM, Scotty Edmonds
>>>>> <scotty@xxxxxxxxxxxxxxxxx> wrote:
>>>>>> Rockstor was running great, I ordered a SuperMicro 24-bay Chassis and decided to power down the machine while I was away. When I turned it back on I got "Failed to read chunk tree" & "open_ctree failed" error (http://i.imgur.com/rGk9M57l.jpg)
>>>>>>
>>>>>> I spoke with support at Rockstor and they recommended I seek help via the mailing list. Here are some details and commands I've run. The specific array is in RAID5 and the label is mainNAS, seagate3x2tb is running perfectly.
>>>>>>
>>>>>> [root@rockstor ~]# btrfs device scan
>>>>>> Scanning for Btrfs filesystems
>>>>>> [root@rockstor ~]#
>>>>>>
>>>>>>
>>>>>>
>>>>>> [root@rockstor ~]# /usr/bin/lsblk -P -o NAME,MODEL,SERIAL,SIZE,TRAN,VENDOR,HCTL,TYPE,FSTYPE,LABEL,UUID
>>>>>> NAME="sda" MODEL="WDC WD30EFRX-68E" SERIAL="WD-WCC4N4KVC39Y" SIZE="2.7T" TRAN="sas" VENDOR="ATA " HCTL="0:0:0:0" TYPE="disk" FSTYPE="btrfs" LABEL="mainNAS" UUID="e8c92d93-fac3-4f83-b3aa-31cb92caafd9"
>>>>>> NAME="sdb" MODEL="WDC WD30EZRX-00M" SERIAL="WD-WCAWZ2551761" SIZE="2.7T" TRAN="sas" VENDOR="ATA " HCTL="0:0:1:0" TYPE="disk" FSTYPE="btrfs" LABEL="mainNAS" UUID="e8c92d93-fac3-4f83-b3aa-31cb92caafd9"
>>>>>> NAME="sdc" MODEL="HGST HDN724030AL" SERIAL="PK2234P9J590GY" SIZE="2.7T" TRAN="sas" VENDOR="ATA " HCTL="0:0:2:0" TYPE="disk" FSTYPE="btrfs" LABEL="mainNAS" UUID="e8c92d93-fac3-4f83-b3aa-31cb92caafd9"
>>>>>> NAME="sdd" MODEL="HGST HDN724030AL" SERIAL="PK2234P9J5WA1Y" SIZE="2.7T" TRAN="sas" VENDOR="ATA " HCTL="0:0:3:0" TYPE="disk" FSTYPE="btrfs" LABEL="mainNAS" UUID="e8c92d93-fac3-4f83-b3aa-31cb92caafd9"
>>>>>> NAME="sde" MODEL="ST3000DM001-1CH1" SERIAL="Z1F517PH" SIZE="2.7T" TRAN="sas" VENDOR="ATA " HCTL="0:0:4:0" TYPE="disk" FSTYPE="btrfs" LABEL="mainNAS" UUID="e8c92d93-fac3-4f83-b3aa-31cb92caafd9"
>>>>>> NAME="sdf" MODEL="ST2000DL003-9VT1" SERIAL="5YD1WK0V" SIZE="1.8T" TRAN="sas" VENDOR="ATA " HCTL="0:0:5:0" TYPE="disk" FSTYPE="btrfs" LABEL="seagate3x2tb" UUID="6ef19043-2d83-4ff1-b959-b9f3c425cc69"
>>>>>> NAME="sdg" MODEL="ST2000DL003-9VT1" SERIAL="5YD2EBDA" SIZE="1.8T" TRAN="sas" VENDOR="ATA " HCTL="0:0:6:0" TYPE="disk" FSTYPE="btrfs" LABEL="seagate3x2tb" UUID="6ef19043-2d83-4ff1-b959-b9f3c425cc69"
>>>>>> NAME="sdh" MODEL="ST2000DL003-9VT1" SERIAL="5YD2L28Z" SIZE="1.8T" TRAN="sas" VENDOR="ATA " HCTL="0:0:7:0" TYPE="disk" FSTYPE="btrfs" LABEL="seagate3x2tb" UUID="6ef19043-2d83-4ff1-b959-b9f3c425cc69"
>>>>>> NAME="sdi" MODEL="INTEL SSDSA2CW08" SERIAL="CVPR1330019Y080BGN" SIZE="74.5G" TRAN="sata" VENDOR="ATA " HCTL="1:0:0:0" TYPE="disk" FSTYPE="" LABEL="" UUID=""
>>>>>> NAME="sdi1" MODEL="" SERIAL="" SIZE="500M" TRAN="" VENDOR="" HCTL="" TYPE="part" FSTYPE="ext4" LABEL="" UUID="53aabf2f-5e28-4a18-922f-b0767a77a8ec"
>>>>>> NAME="sdi2" MODEL="" SERIAL="" SIZE="7.3G" TRAN="" VENDOR="" HCTL="" TYPE="part" FSTYPE="swap" LABEL="" UUID="bf9e72c7-7d72-4a33-a5eb-0a0013033234"
>>>>>> NAME="sdi3" MODEL="" SERIAL="" SIZE="66.8G" TRAN="" VENDOR="" HCTL="" TYPE="part" FSTYPE="btrfs" LABEL="rockstor_rockstor" UUID="3533171e-d95b-4491-aa4c-cc956536a1c3"
>>>>>> [root@rockstor ~]#
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>> [root@rockstor ~]# btrfs fi show
>>>>>> Label: 'rockstor_rockstor' uuid: 3533171e-d95b-4491-aa4c-cc956536a1c3
>>>>>> Total devices 1 FS bytes used 2.17GiB
>>>>>> devid 1 size 66.79GiB used 7.02GiB path /dev/sdi3
>>>>>>
>>>>>> Label: 'seagate3x2tb' uuid: 6ef19043-2d83-4ff1-b959-b9f3c425cc69
>>>>>> Total devices 3 FS bytes used 1.13TiB
>>>>>> devid 1 size 1.82TiB used 595.03GiB path /dev/sdh
>>>>>> devid 2 size 1.82TiB used 595.01GiB path /dev/sdf
>>>>>> devid 3 size 1.82TiB used 595.01GiB path /dev/sdg
>>>>>>
>>>>>> Label: 'mainNAS' uuid: e8c92d93-fac3-4f83-b3aa-31cb92caafd9
>>>>>> Total devices 5 FS bytes used 5.43TiB
>>>>>> devid 1 size 2.73TiB used 1.36TiB path /dev/sdd
>>>>>> devid 2 size 2.73TiB used 1.36TiB path /dev/sdc
>>>>>> devid 3 size 2.73TiB used 1.36TiB path /dev/sda
>>>>>> devid 4 size 2.73TiB used 1.36TiB path /dev/sde
>>>>>> devid 5 size 2.73TiB used 1.36TiB path /dev/sdb
>>>>>>
>>>>>>
>>>>>> btrfs-progs v4.2.1
>>>>>>
>>>>>> I'm unable to mount any of the drives that are in the mainNAS array, this is the error when I try to mount all of the drives degraded.
>>>>>>
>>>>>> [root@rockstor ~]# mount -v -o degraded /dev/sdd /mnt2/mainNAS
>>>>>> mount: wrong fs type, bad option, bad superblock on /dev/sdd,
>>>>>> missing codepage or helper program, or other error
>>>>>> In some cases useful info is found in syslog - try
>>>>>> dmesg | tail or so.
>>>>>> [root@rockstor ~]#
>>>>>>
>>>>>> I haven't given up hope yet as the "btrfs fi show" gives me all the correct data and I ran chunk-recover and superblocks all report back as good.
>>>>>>
>>>>>>
>>>>>> Thanks for your help, let me know if you need any further information.
>>>>>>
>>>>>> Thanks,
>>>>>>
>>>>>> Scotty Edmonds
>>>>>> Scotty@xxxxxxxxxxxxxxxxx
>>
>> --
>> Hugo Mills | "How deep will this sub go?"
>> hugo@... carfax.org.uk | "Oh, she'll go all the way to the bottom if we don't
>> http://carfax.org.uk/ | stop her."
>> PGP: E2AB1DE4 | U571
>> --
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