Can't mount btrfs volume on rbd

Can't mount btrfs volume on rbd

[Steve Dainard]

Hello,

I'm getting an error when attempting to mount a volume on a host that
was forceably powered off:

# mount /dev/rbd4 climate-downscale-CMIP5/
mount: mount /dev/rbd4 on /mnt/climate-downscale-CMIP5 failed: Stale file handle

/var/log/messages:
Jun 10 15:31:07 node1 kernel: rbd4: unknown partition table

# parted /dev/rbd4 print
Model: Unknown (unknown)
Disk /dev/rbd4: 36.5TB
Sector size (logical/physical): 512B/512B
Partition Table: loop
Disk Flags:

Number  Start  End     Size    File system  Flags
 1      0.00B  36.5TB  36.5TB  btrfs

# btrfs check --repair /dev/rbd4
enabling repair mode
Checking filesystem on /dev/rbd4
UUID: dfe6b0c8-2866-4318-abc2-e1e75c891a5e
checking extents
cmds-check.c:2274: check_owner_ref: Assertion `rec->is_root` failed.
btrfs[0x4175cc]
btrfs[0x41b873]
btrfs[0x41c3fe]
btrfs[0x41dc1d]
btrfs[0x406922]


OS: CentOS 7.1
btrfs-progs: 3.16.2
Ceph: version: 0.94.1/CentOS 7.1

I haven't found any references to 'stale file handle' on btrfs.

The underlying block device is ceph rbd, so I've posted to both lists
for any feedback. Also once I reformatted btrfs I didn't get a mount
error.

The btrfs volume has been reformatted so I won't be able to do much
post mortem but I'm wondering if anyone has some insight.

Thanks,
Steve

Re: Can't mount btrfs volume on rbd

[Qu Wenruo]

-------- Original Message  --------
Subject: Can't mount btrfs volume on rbd
From: Steve Dainard <sdainard@spd1.com>
To: <linux-btrfs@vger.kernel.org>
Date: 2015年06月11日 23:26

> Hello,
>
> I'm getting an error when attempting to mount a volume on a host that
> was forceably powered off:
>
> # mount /dev/rbd4 climate-downscale-CMIP5/
> mount: mount /dev/rbd4 on /mnt/climate-downscale-CMIP5 failed: Stale file handle
>
> /var/log/messages:
> Jun 10 15:31:07 node1 kernel: rbd4: unknown partition table
>
> # parted /dev/rbd4 print
> Model: Unknown (unknown)
> Disk /dev/rbd4: 36.5TB
> Sector size (logical/physical): 512B/512B
> Partition Table: loop
> Disk Flags:
>
> Number  Start  End     Size    File system  Flags
>   1      0.00B  36.5TB  36.5TB  btrfs
>
> # btrfs check --repair /dev/rbd4
> enabling repair mode
> Checking filesystem on /dev/rbd4
> UUID: dfe6b0c8-2866-4318-abc2-e1e75c891a5e
> checking extents
> cmds-check.c:2274: check_owner_ref: Assertion `rec->is_root` failed.
> btrfs[0x4175cc]
> btrfs[0x41b873]
> btrfs[0x41c3fe]
> btrfs[0x41dc1d]
> btrfs[0x406922]
>
>
> OS: CentOS 7.1
> btrfs-progs: 3.16.2
The btrfs-progs seems quite old, and the above btrfsck error seems quite
possible related to the old version.

Would you please upgrade btrfs-progs to 4.0 and see what will happen?
Hopes it can give better info.

BTW, it's a good idea to call btrfs-debug-tree /dev/rbd4 to see the output.

Thanks
Qu.
> Ceph: version: 0.94.1/CentOS 7.1
>
> I haven't found any references to 'stale file handle' on btrfs.
>
> The underlying block device is ceph rbd, so I've posted to both lists
> for any feedback. Also once I reformatted btrfs I didn't get a mount
> error.
>
> The btrfs volume has been reformatted so I won't be able to do much
> post mortem but I'm wondering if anyone has some insight.
>
> Thanks,
> Steve
> --
> To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>

Re: Can't mount btrfs volume on rbd

[Steve Dainard]

Hi Qu,

I have another volume with the same error, btrfs-debug-tree output
from btrfs-progs 4.0.1 is here: http://pastebin.com/k3R3bngE

I'm not sure how to interpret the output, but the exit status is 0 so
it looks like btrfs doesn't think there's an issue with the file
system.

I get the same mount error with options ro,recovery.

On Fri, Jun 12, 2015 at 12:23 AM, Qu Wenruo <quwenruo@cn.fujitsu.com> wrote:
>
>
> -------- Original Message  --------
> Subject: Can't mount btrfs volume on rbd
> From: Steve Dainard <sdainard@spd1.com>
> To: <linux-btrfs@vger.kernel.org>
> Date: 2015年06月11日 23:26
>
>> Hello,
>>
>> I'm getting an error when attempting to mount a volume on a host that
>> was forceably powered off:
>>
>> # mount /dev/rbd4 climate-downscale-CMIP5/
>> mount: mount /dev/rbd4 on /mnt/climate-downscale-CMIP5 failed: Stale file
>> handle
>>
>> /var/log/messages:
>> Jun 10 15:31:07 node1 kernel: rbd4: unknown partition table
>>
>> # parted /dev/rbd4 print
>> Model: Unknown (unknown)
>> Disk /dev/rbd4: 36.5TB
>> Sector size (logical/physical): 512B/512B
>> Partition Table: loop
>> Disk Flags:
>>
>> Number  Start  End     Size    File system  Flags
>>   1      0.00B  36.5TB  36.5TB  btrfs
>>
>> # btrfs check --repair /dev/rbd4
>> enabling repair mode
>> Checking filesystem on /dev/rbd4
>> UUID: dfe6b0c8-2866-4318-abc2-e1e75c891a5e
>> checking extents
>> cmds-check.c:2274: check_owner_ref: Assertion `rec->is_root` failed.
>> btrfs[0x4175cc]
>> btrfs[0x41b873]
>> btrfs[0x41c3fe]
>> btrfs[0x41dc1d]
>> btrfs[0x406922]
>>
>>
>> OS: CentOS 7.1
>> btrfs-progs: 3.16.2
>
> The btrfs-progs seems quite old, and the above btrfsck error seems quite
> possible related to the old version.
>
> Would you please upgrade btrfs-progs to 4.0 and see what will happen?
> Hopes it can give better info.
>
> BTW, it's a good idea to call btrfs-debug-tree /dev/rbd4 to see the output.
>
> Thanks
> Qu.
>>
>> Ceph: version: 0.94.1/CentOS 7.1
>>
>> I haven't found any references to 'stale file handle' on btrfs.
>>
>> The underlying block device is ceph rbd, so I've posted to both lists
>> for any feedback. Also once I reformatted btrfs I didn't get a mount
>> error.
>>
>> The btrfs volume has been reformatted so I won't be able to do much
>> post mortem but I'm wondering if anyone has some insight.
>>
>> Thanks,
>> Steve
>> --
>> To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in
>> the body of a message to majordomo@vger.kernel.org
>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>>
>

Re: Can't mount btrfs volume on rbd

[Qu Wenruo]

The debug result seems valid.
So I'm afraid the problem is not in btrfs.

Would your please try the following 2 things to eliminate btrfs problems?

1) btrfsck from 4.0.1 on the rbd

If assert still happens, please update the image of the volume(dd 
image), to help us improve btrfs-progs.

2) btrfs-image dump and rebuilt the fs into other place.

# btrfs-image <RBD_DEV> <tmp_file1> -c9
# btrfs-image -r <tmp_file1> <tmp_file2>
# mount <tmp_file2> <mnt>

This will dump all metadata from <RBD_DEV> to <tmp_file1>,
and then use <tmp_file1> to rebuild a image called <tmp_file2>.

If <tmp_file2> can be mounted, then the metadata in the RBD device is 
completely OK, and we can make conclusion the problem is not caused by 
btrfs.(maybe ceph?)

BTW, all the commands are recommended to be executed on the device which 
you get the debug info from.
As it's a small and almost empty device, so commands execution should be 
quite fast on it.

Thanks,
Qu

在 2015年06月13日 00:09, Steve Dainard 写道:
> Hi Qu,
>
> I have another volume with the same error, btrfs-debug-tree output
> from btrfs-progs 4.0.1 is here: http://pastebin.com/k3R3bngE
>
> I'm not sure how to interpret the output, but the exit status is 0 so
> it looks like btrfs doesn't think there's an issue with the file
> system.
>
> I get the same mount error with options ro,recovery.
>
> On Fri, Jun 12, 2015 at 12:23 AM, Qu Wenruo <quwenruo@cn.fujitsu.com> wrote:
>>
>>
>> -------- Original Message  --------
>> Subject: Can't mount btrfs volume on rbd
>> From: Steve Dainard <sdainard@spd1.com>
>> To: <linux-btrfs@vger.kernel.org>
>> Date: 2015年06月11日 23:26
>>
>>> Hello,
>>>
>>> I'm getting an error when attempting to mount a volume on a host that
>>> was forceably powered off:
>>>
>>> # mount /dev/rbd4 climate-downscale-CMIP5/
>>> mount: mount /dev/rbd4 on /mnt/climate-downscale-CMIP5 failed: Stale file
>>> handle
>>>
>>> /var/log/messages:
>>> Jun 10 15:31:07 node1 kernel: rbd4: unknown partition table
>>>
>>> # parted /dev/rbd4 print
>>> Model: Unknown (unknown)
>>> Disk /dev/rbd4: 36.5TB
>>> Sector size (logical/physical): 512B/512B
>>> Partition Table: loop
>>> Disk Flags:
>>>
>>> Number  Start  End     Size    File system  Flags
>>>    1      0.00B  36.5TB  36.5TB  btrfs
>>>
>>> # btrfs check --repair /dev/rbd4
>>> enabling repair mode
>>> Checking filesystem on /dev/rbd4
>>> UUID: dfe6b0c8-2866-4318-abc2-e1e75c891a5e
>>> checking extents
>>> cmds-check.c:2274: check_owner_ref: Assertion `rec->is_root` failed.
>>> btrfs[0x4175cc]
>>> btrfs[0x41b873]
>>> btrfs[0x41c3fe]
>>> btrfs[0x41dc1d]
>>> btrfs[0x406922]
>>>
>>>
>>> OS: CentOS 7.1
>>> btrfs-progs: 3.16.2
>>
>> The btrfs-progs seems quite old, and the above btrfsck error seems quite
>> possible related to the old version.
>>
>> Would you please upgrade btrfs-progs to 4.0 and see what will happen?
>> Hopes it can give better info.
>>
>> BTW, it's a good idea to call btrfs-debug-tree /dev/rbd4 to see the output.
>>
>> Thanks
>> Qu.
>>>
>>> Ceph: version: 0.94.1/CentOS 7.1
>>>
>>> I haven't found any references to 'stale file handle' on btrfs.
>>>
>>> The underlying block device is ceph rbd, so I've posted to both lists
>>> for any feedback. Also once I reformatted btrfs I didn't get a mount
>>> error.
>>>
>>> The btrfs volume has been reformatted so I won't be able to do much
>>> post mortem but I'm wondering if anyone has some insight.
>>>
>>> Thanks,
>>> Steve
>>> --
>>> To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in
>>> the body of a message to majordomo@vger.kernel.org
>>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>>>
>>

Re: Can't mount btrfs volume on rbd

[Steve Dainard]

Hi Qu,

# btrfs --version
btrfs-progs v4.0.1
# btrfs check /dev/rbd30
Checking filesystem on /dev/rbd30
UUID: 1bb22a03-bc25-466f-b078-c66c6f6a6d28
checking extents
cmds-check.c:3735: check_owner_ref: Assertion `rec->is_root` failed.
btrfs[0x41aee6]
btrfs[0x423f5d]
btrfs[0x424c99]
btrfs[0x4258f6]
btrfs(cmd_check+0x14a3)[0x42893d]
btrfs(main+0x15d)[0x409c71]
/lib64/libc.so.6(__libc_start_main+0xf5)[0x7f29ce437af5]
btrfs[0x409829]

# btrfs-image /dev/rbd30 rbd30.image -c9
# btrfs-image -r rbd30.image rbd30.image.2
# mount rbd30.image.2 temp
mount: mount /dev/loop0 on /mnt/temp failed: Stale file handle

I have a suspicion this was caused by pacemaker starting
ceph/filesystem resources on two nodes at the same time, I haven't
been able to replicate the issue after hard poweroff if ceph/btrfs are
not being controlled by pacemaker.

Thanks for your help.



On Mon, Jun 15, 2015 at 1:06 AM, Qu Wenruo <quwenruo@cn.fujitsu.com> wrote:
> The debug result seems valid.
> So I'm afraid the problem is not in btrfs.
>
> Would your please try the following 2 things to eliminate btrfs problems?
>
> 1) btrfsck from 4.0.1 on the rbd
>
> If assert still happens, please update the image of the volume(dd image), to
> help us improve btrfs-progs.
>
> 2) btrfs-image dump and rebuilt the fs into other place.
>
> # btrfs-image <RBD_DEV> <tmp_file1> -c9
> # btrfs-image -r <tmp_file1> <tmp_file2>
> # mount <tmp_file2> <mnt>
>
> This will dump all metadata from <RBD_DEV> to <tmp_file1>,
> and then use <tmp_file1> to rebuild a image called <tmp_file2>.
>
> If <tmp_file2> can be mounted, then the metadata in the RBD device is
> completely OK, and we can make conclusion the problem is not caused by
> btrfs.(maybe ceph?)
>
> BTW, all the commands are recommended to be executed on the device which you
> get the debug info from.
> As it's a small and almost empty device, so commands execution should be
> quite fast on it.
>
> Thanks,
> Qu
>
>
> 在 2015年06月13日 00:09, Steve Dainard 写道:
>>
>> Hi Qu,
>>
>> I have another volume with the same error, btrfs-debug-tree output
>> from btrfs-progs 4.0.1 is here: http://pastebin.com/k3R3bngE
>>
>> I'm not sure how to interpret the output, but the exit status is 0 so
>> it looks like btrfs doesn't think there's an issue with the file
>> system.
>>
>> I get the same mount error with options ro,recovery.
>>
>> On Fri, Jun 12, 2015 at 12:23 AM, Qu Wenruo <quwenruo@cn.fujitsu.com>
>> wrote:
>>>
>>>
>>>
>>> -------- Original Message  --------
>>> Subject: Can't mount btrfs volume on rbd
>>> From: Steve Dainard <sdainard@spd1.com>
>>> To: <linux-btrfs@vger.kernel.org>
>>> Date: 2015年06月11日 23:26
>>>
>>>> Hello,
>>>>
>>>> I'm getting an error when attempting to mount a volume on a host that
>>>> was forceably powered off:
>>>>
>>>> # mount /dev/rbd4 climate-downscale-CMIP5/
>>>> mount: mount /dev/rbd4 on /mnt/climate-downscale-CMIP5 failed: Stale
>>>> file
>>>> handle
>>>>
>>>> /var/log/messages:
>>>> Jun 10 15:31:07 node1 kernel: rbd4: unknown partition table
>>>>
>>>> # parted /dev/rbd4 print
>>>> Model: Unknown (unknown)
>>>> Disk /dev/rbd4: 36.5TB
>>>> Sector size (logical/physical): 512B/512B
>>>> Partition Table: loop
>>>> Disk Flags:
>>>>
>>>> Number  Start  End     Size    File system  Flags
>>>>    1      0.00B  36.5TB  36.5TB  btrfs
>>>>
>>>> # btrfs check --repair /dev/rbd4
>>>> enabling repair mode
>>>> Checking filesystem on /dev/rbd4
>>>> UUID: dfe6b0c8-2866-4318-abc2-e1e75c891a5e
>>>> checking extents
>>>> cmds-check.c:2274: check_owner_ref: Assertion `rec->is_root` failed.
>>>> btrfs[0x4175cc]
>>>> btrfs[0x41b873]
>>>> btrfs[0x41c3fe]
>>>> btrfs[0x41dc1d]
>>>> btrfs[0x406922]
>>>>
>>>>
>>>> OS: CentOS 7.1
>>>> btrfs-progs: 3.16.2
>>>
>>>
>>> The btrfs-progs seems quite old, and the above btrfsck error seems quite
>>> possible related to the old version.
>>>
>>> Would you please upgrade btrfs-progs to 4.0 and see what will happen?
>>> Hopes it can give better info.
>>>
>>> BTW, it's a good idea to call btrfs-debug-tree /dev/rbd4 to see the
>>> output.
>>>
>>> Thanks
>>> Qu.
>>>>
>>>>
>>>> Ceph: version: 0.94.1/CentOS 7.1
>>>>
>>>> I haven't found any references to 'stale file handle' on btrfs.
>>>>
>>>> The underlying block device is ceph rbd, so I've posted to both lists
>>>> for any feedback. Also once I reformatted btrfs I didn't get a mount
>>>> error.
>>>>
>>>> The btrfs volume has been reformatted so I won't be able to do much
>>>> post mortem but I'm wondering if anyone has some insight.
>>>>
>>>> Thanks,
>>>> Steve
>>>> --
>>>> To unsubscribe from this list: send the line "unsubscribe linux-btrfs"
>>>> in
>>>> the body of a message to majordomo@vger.kernel.org
>>>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>>>>
>>>
>

Re: Can't mount btrfs volume on rbd

[Qu Wenruo]

Steve Dainard wrote on 2015/06/15 09:19 -0700:
> Hi Qu,
>
> # btrfs --version
> btrfs-progs v4.0.1
> # btrfs check /dev/rbd30
> Checking filesystem on /dev/rbd30
> UUID: 1bb22a03-bc25-466f-b078-c66c6f6a6d28
> checking extents
> cmds-check.c:3735: check_owner_ref: Assertion `rec->is_root` failed.
> btrfs[0x41aee6]
> btrfs[0x423f5d]
> btrfs[0x424c99]
> btrfs[0x4258f6]
> btrfs(cmd_check+0x14a3)[0x42893d]
> btrfs(main+0x15d)[0x409c71]
> /lib64/libc.so.6(__libc_start_main+0xf5)[0x7f29ce437af5]
> btrfs[0x409829]
>
> # btrfs-image /dev/rbd30 rbd30.image -c9
> # btrfs-image -r rbd30.image rbd30.image.2
> # mount rbd30.image.2 temp
> mount: mount /dev/loop0 on /mnt/temp failed: Stale file handle
OK, my assumption are all wrong.

I'd better check the debug-tree output more carefully.

BTW, the rbd30 is the block device which you took the debug-tree output?

If so, would you please do a dd dump of it and send it to me?
If it contains important/secret info, just forget this.

Maybe I can improve the btrfsck tool to fix it.

>
> I have a suspicion this was caused by pacemaker starting
> ceph/filesystem resources on two nodes at the same time,I haven't
> been able to replicate the issue after hard poweroff if ceph/btrfs are
> not being controlled by pacemaker.
Did you mean mount the same device on different system?

Thanks,
Qu
>
> Thanks for your help.
>
>
>
> On Mon, Jun 15, 2015 at 1:06 AM, Qu Wenruo <quwenruo@cn.fujitsu.com> wrote:
>> The debug result seems valid.
>> So I'm afraid the problem is not in btrfs.
>>
>> Would your please try the following 2 things to eliminate btrfs problems?
>>
>> 1) btrfsck from 4.0.1 on the rbd
>>
>> If assert still happens, please update the image of the volume(dd image), to
>> help us improve btrfs-progs.
>>
>> 2) btrfs-image dump and rebuilt the fs into other place.
>>
>> # btrfs-image <RBD_DEV> <tmp_file1> -c9
>> # btrfs-image -r <tmp_file1> <tmp_file2>
>> # mount <tmp_file2> <mnt>
>>
>> This will dump all metadata from <RBD_DEV> to <tmp_file1>,
>> and then use <tmp_file1> to rebuild a image called <tmp_file2>.
>>
>> If <tmp_file2> can be mounted, then the metadata in the RBD device is
>> completely OK, and we can make conclusion the problem is not caused by
>> btrfs.(maybe ceph?)
>>
>> BTW, all the commands are recommended to be executed on the device which you
>> get the debug info from.
>> As it's a small and almost empty device, so commands execution should be
>> quite fast on it.
>>
>> Thanks,
>> Qu
>>
>>
>> 在 2015年06月13日 00:09, Steve Dainard 写道:
>>>
>>> Hi Qu,
>>>
>>> I have another volume with the same error, btrfs-debug-tree output
>>> from btrfs-progs 4.0.1 is here: http://pastebin.com/k3R3bngE
>>>
>>> I'm not sure how to interpret the output, but the exit status is 0 so
>>> it looks like btrfs doesn't think there's an issue with the file
>>> system.
>>>
>>> I get the same mount error with options ro,recovery.
>>>
>>> On Fri, Jun 12, 2015 at 12:23 AM, Qu Wenruo <quwenruo@cn.fujitsu.com>
>>> wrote:
>>>>
>>>>
>>>>
>>>> -------- Original Message  --------
>>>> Subject: Can't mount btrfs volume on rbd
>>>> From: Steve Dainard <sdainard@spd1.com>
>>>> To: <linux-btrfs@vger.kernel.org>
>>>> Date: 2015年06月11日 23:26
>>>>
>>>>> Hello,
>>>>>
>>>>> I'm getting an error when attempting to mount a volume on a host that
>>>>> was forceably powered off:
>>>>>
>>>>> # mount /dev/rbd4 climate-downscale-CMIP5/
>>>>> mount: mount /dev/rbd4 on /mnt/climate-downscale-CMIP5 failed: Stale
>>>>> file
>>>>> handle
>>>>>
>>>>> /var/log/messages:
>>>>> Jun 10 15:31:07 node1 kernel: rbd4: unknown partition table
>>>>>
>>>>> # parted /dev/rbd4 print
>>>>> Model: Unknown (unknown)
>>>>> Disk /dev/rbd4: 36.5TB
>>>>> Sector size (logical/physical): 512B/512B
>>>>> Partition Table: loop
>>>>> Disk Flags:
>>>>>
>>>>> Number  Start  End     Size    File system  Flags
>>>>>     1      0.00B  36.5TB  36.5TB  btrfs
>>>>>
>>>>> # btrfs check --repair /dev/rbd4
>>>>> enabling repair mode
>>>>> Checking filesystem on /dev/rbd4
>>>>> UUID: dfe6b0c8-2866-4318-abc2-e1e75c891a5e
>>>>> checking extents
>>>>> cmds-check.c:2274: check_owner_ref: Assertion `rec->is_root` failed.
>>>>> btrfs[0x4175cc]
>>>>> btrfs[0x41b873]
>>>>> btrfs[0x41c3fe]
>>>>> btrfs[0x41dc1d]
>>>>> btrfs[0x406922]
>>>>>
>>>>>
>>>>> OS: CentOS 7.1
>>>>> btrfs-progs: 3.16.2
>>>>
>>>>
>>>> The btrfs-progs seems quite old, and the above btrfsck error seems quite
>>>> possible related to the old version.
>>>>
>>>> Would you please upgrade btrfs-progs to 4.0 and see what will happen?
>>>> Hopes it can give better info.
>>>>
>>>> BTW, it's a good idea to call btrfs-debug-tree /dev/rbd4 to see the
>>>> output.
>>>>
>>>> Thanks
>>>> Qu.
>>>>>
>>>>>
>>>>> Ceph: version: 0.94.1/CentOS 7.1
>>>>>
>>>>> I haven't found any references to 'stale file handle' on btrfs.
>>>>>
>>>>> The underlying block device is ceph rbd, so I've posted to both lists
>>>>> for any feedback. Also once I reformatted btrfs I didn't get a mount
>>>>> error.
>>>>>
>>>>> The btrfs volume has been reformatted so I won't be able to do much
>>>>> post mortem but I'm wondering if anyone has some insight.
>>>>>
>>>>> Thanks,
>>>>> Steve
>>>>> --
>>>>> To unsubscribe from this list: send the line "unsubscribe linux-btrfs"
>>>>> in
>>>>> the body of a message to majordomo@vger.kernel.org
>>>>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>>>>>
>>>>
>>

Re: Can't mount btrfs volume on rbd

[Steve Dainard]

Hi Qu,

I ran into this issue again, without pacemaker involved, so I'm really
not sure what is triggering this.

There is no content at all on this disk, basically it was created with
a btrfs filesystem, mounted, and now after some reboots later (and
possibly hard resets) won't mount with a stale file handle error.

I've DD'd the 10G disk and tarballed it to 10MB, I'll send it to you
in another email so the attachment doesn't spam the list.

Thanks,
Steve

On Mon, Jun 15, 2015 at 6:27 PM, Qu Wenruo <quwenruo@cn.fujitsu.com> wrote:
>
>
> Steve Dainard wrote on 2015/06/15 09:19 -0700:
>>
>> Hi Qu,
>>
>> # btrfs --version
>> btrfs-progs v4.0.1
>> # btrfs check /dev/rbd30
>> Checking filesystem on /dev/rbd30
>> UUID: 1bb22a03-bc25-466f-b078-c66c6f6a6d28
>> checking extents
>> cmds-check.c:3735: check_owner_ref: Assertion `rec->is_root` failed.
>> btrfs[0x41aee6]
>> btrfs[0x423f5d]
>> btrfs[0x424c99]
>> btrfs[0x4258f6]
>> btrfs(cmd_check+0x14a3)[0x42893d]
>> btrfs(main+0x15d)[0x409c71]
>> /lib64/libc.so.6(__libc_start_main+0xf5)[0x7f29ce437af5]
>> btrfs[0x409829]
>>
>> # btrfs-image /dev/rbd30 rbd30.image -c9
>> # btrfs-image -r rbd30.image rbd30.image.2
>> # mount rbd30.image.2 temp
>> mount: mount /dev/loop0 on /mnt/temp failed: Stale file handle
>
> OK, my assumption are all wrong.
>
> I'd better check the debug-tree output more carefully.
>
> BTW, the rbd30 is the block device which you took the debug-tree output?
>
> If so, would you please do a dd dump of it and send it to me?
> If it contains important/secret info, just forget this.
>
> Maybe I can improve the btrfsck tool to fix it.
>
>>
>> I have a suspicion this was caused by pacemaker starting
>> ceph/filesystem resources on two nodes at the same time,I haven't
>> been able to replicate the issue after hard poweroff if ceph/btrfs are
>> not being controlled by pacemaker.
>
> Did you mean mount the same device on different system?
>
> Thanks,
> Qu
>
>>
>> Thanks for your help.
>>
>>
>>
>> On Mon, Jun 15, 2015 at 1:06 AM, Qu Wenruo <quwenruo@cn.fujitsu.com>
>> wrote:
>>>
>>> The debug result seems valid.
>>> So I'm afraid the problem is not in btrfs.
>>>
>>> Would your please try the following 2 things to eliminate btrfs problems?
>>>
>>> 1) btrfsck from 4.0.1 on the rbd
>>>
>>> If assert still happens, please update the image of the volume(dd image),
>>> to
>>> help us improve btrfs-progs.
>>>
>>> 2) btrfs-image dump and rebuilt the fs into other place.
>>>
>>> # btrfs-image <RBD_DEV> <tmp_file1> -c9
>>> # btrfs-image -r <tmp_file1> <tmp_file2>
>>> # mount <tmp_file2> <mnt>
>>>
>>> This will dump all metadata from <RBD_DEV> to <tmp_file1>,
>>> and then use <tmp_file1> to rebuild a image called <tmp_file2>.
>>>
>>> If <tmp_file2> can be mounted, then the metadata in the RBD device is
>>> completely OK, and we can make conclusion the problem is not caused by
>>> btrfs.(maybe ceph?)
>>>
>>> BTW, all the commands are recommended to be executed on the device which
>>> you
>>> get the debug info from.
>>> As it's a small and almost empty device, so commands execution should be
>>> quite fast on it.
>>>
>>> Thanks,
>>> Qu
>>>
>>>
>>> 在 2015年06月13日 00:09, Steve Dainard 写道:
>>>>
>>>>
>>>> Hi Qu,
>>>>
>>>> I have another volume with the same error, btrfs-debug-tree output
>>>> from btrfs-progs 4.0.1 is here: http://pastebin.com/k3R3bngE
>>>>
>>>> I'm not sure how to interpret the output, but the exit status is 0 so
>>>> it looks like btrfs doesn't think there's an issue with the file
>>>> system.
>>>>
>>>> I get the same mount error with options ro,recovery.
>>>>
>>>> On Fri, Jun 12, 2015 at 12:23 AM, Qu Wenruo <quwenruo@cn.fujitsu.com>
>>>> wrote:
>>>>>
>>>>>
>>>>>
>>>>>
>>>>> -------- Original Message  --------
>>>>> Subject: Can't mount btrfs volume on rbd
>>>>> From: Steve Dainard <sdainard@spd1.com>
>>>>> To: <linux-btrfs@vger.kernel.org>
>>>>> Date: 2015年06月11日 23:26
>>>>>
>>>>>> Hello,
>>>>>>
>>>>>> I'm getting an error when attempting to mount a volume on a host that
>>>>>> was forceably powered off:
>>>>>>
>>>>>> # mount /dev/rbd4 climate-downscale-CMIP5/
>>>>>> mount: mount /dev/rbd4 on /mnt/climate-downscale-CMIP5 failed: Stale
>>>>>> file
>>>>>> handle
>>>>>>
>>>>>> /var/log/messages:
>>>>>> Jun 10 15:31:07 node1 kernel: rbd4: unknown partition table
>>>>>>
>>>>>> # parted /dev/rbd4 print
>>>>>> Model: Unknown (unknown)
>>>>>> Disk /dev/rbd4: 36.5TB
>>>>>> Sector size (logical/physical): 512B/512B
>>>>>> Partition Table: loop
>>>>>> Disk Flags:
>>>>>>
>>>>>> Number  Start  End     Size    File system  Flags
>>>>>>     1      0.00B  36.5TB  36.5TB  btrfs
>>>>>>
>>>>>> # btrfs check --repair /dev/rbd4
>>>>>> enabling repair mode
>>>>>> Checking filesystem on /dev/rbd4
>>>>>> UUID: dfe6b0c8-2866-4318-abc2-e1e75c891a5e
>>>>>> checking extents
>>>>>> cmds-check.c:2274: check_owner_ref: Assertion `rec->is_root` failed.
>>>>>> btrfs[0x4175cc]
>>>>>> btrfs[0x41b873]
>>>>>> btrfs[0x41c3fe]
>>>>>> btrfs[0x41dc1d]
>>>>>> btrfs[0x406922]
>>>>>>
>>>>>>
>>>>>> OS: CentOS 7.1
>>>>>> btrfs-progs: 3.16.2
>>>>>
>>>>>
>>>>>
>>>>> The btrfs-progs seems quite old, and the above btrfsck error seems
>>>>> quite
>>>>> possible related to the old version.
>>>>>
>>>>> Would you please upgrade btrfs-progs to 4.0 and see what will happen?
>>>>> Hopes it can give better info.
>>>>>
>>>>> BTW, it's a good idea to call btrfs-debug-tree /dev/rbd4 to see the
>>>>> output.
>>>>>
>>>>> Thanks
>>>>> Qu.
>>>>>>
>>>>>>
>>>>>>
>>>>>> Ceph: version: 0.94.1/CentOS 7.1
>>>>>>
>>>>>> I haven't found any references to 'stale file handle' on btrfs.
>>>>>>
>>>>>> The underlying block device is ceph rbd, so I've posted to both lists
>>>>>> for any feedback. Also once I reformatted btrfs I didn't get a mount
>>>>>> error.
>>>>>>
>>>>>> The btrfs volume has been reformatted so I won't be able to do much
>>>>>> post mortem but I'm wondering if anyone has some insight.
>>>>>>
>>>>>> Thanks,
>>>>>> Steve
>>>>>> --
>>>>>> To unsubscribe from this list: send the line "unsubscribe linux-btrfs"
>>>>>> in
>>>>>> the body of a message to majordomo@vger.kernel.org
>>>>>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>>>>>>
>>>>>
>>>
>

Re: Can't mount btrfs volume on rbd

[Qu Wenruo]

Thanks a lot Steve!

With this binary dump, we can find out what's the cause of your problem 
and makes btrfsck handle and repair it.

Further more, this provides a good hint on what's going wrong in kernel.

I'll start investigating this right now.

Thanks,
Qu

Steve Dainard wrote on 2015/07/13 13:22 -0700:
> Hi Qu,
>
> I ran into this issue again, without pacemaker involved, so I'm really
> not sure what is triggering this.
>
> There is no content at all on this disk, basically it was created with
> a btrfs filesystem, mounted, and now after some reboots later (and
> possibly hard resets) won't mount with a stale file handle error.
>
> I've DD'd the 10G disk and tarballed it to 10MB, I'll send it to you
> in another email so the attachment doesn't spam the list.
>
> Thanks,
> Steve
>
> On Mon, Jun 15, 2015 at 6:27 PM, Qu Wenruo <quwenruo@cn.fujitsu.com> wrote:
>>
>>
>> Steve Dainard wrote on 2015/06/15 09:19 -0700:
>>>
>>> Hi Qu,
>>>
>>> # btrfs --version
>>> btrfs-progs v4.0.1
>>> # btrfs check /dev/rbd30
>>> Checking filesystem on /dev/rbd30
>>> UUID: 1bb22a03-bc25-466f-b078-c66c6f6a6d28
>>> checking extents
>>> cmds-check.c:3735: check_owner_ref: Assertion `rec->is_root` failed.
>>> btrfs[0x41aee6]
>>> btrfs[0x423f5d]
>>> btrfs[0x424c99]
>>> btrfs[0x4258f6]
>>> btrfs(cmd_check+0x14a3)[0x42893d]
>>> btrfs(main+0x15d)[0x409c71]
>>> /lib64/libc.so.6(__libc_start_main+0xf5)[0x7f29ce437af5]
>>> btrfs[0x409829]
>>>
>>> # btrfs-image /dev/rbd30 rbd30.image -c9
>>> # btrfs-image -r rbd30.image rbd30.image.2
>>> # mount rbd30.image.2 temp
>>> mount: mount /dev/loop0 on /mnt/temp failed: Stale file handle
>>
>> OK, my assumption are all wrong.
>>
>> I'd better check the debug-tree output more carefully.
>>
>> BTW, the rbd30 is the block device which you took the debug-tree output?
>>
>> If so, would you please do a dd dump of it and send it to me?
>> If it contains important/secret info, just forget this.
>>
>> Maybe I can improve the btrfsck tool to fix it.
>>
>>>
>>> I have a suspicion this was caused by pacemaker starting
>>> ceph/filesystem resources on two nodes at the same time,I haven't
>>> been able to replicate the issue after hard poweroff if ceph/btrfs are
>>> not being controlled by pacemaker.
>>
>> Did you mean mount the same device on different system?
>>
>> Thanks,
>> Qu
>>
>>>
>>> Thanks for your help.
>>>
>>>
>>>
>>> On Mon, Jun 15, 2015 at 1:06 AM, Qu Wenruo <quwenruo@cn.fujitsu.com>
>>> wrote:
>>>>
>>>> The debug result seems valid.
>>>> So I'm afraid the problem is not in btrfs.
>>>>
>>>> Would your please try the following 2 things to eliminate btrfs problems?
>>>>
>>>> 1) btrfsck from 4.0.1 on the rbd
>>>>
>>>> If assert still happens, please update the image of the volume(dd image),
>>>> to
>>>> help us improve btrfs-progs.
>>>>
>>>> 2) btrfs-image dump and rebuilt the fs into other place.
>>>>
>>>> # btrfs-image <RBD_DEV> <tmp_file1> -c9
>>>> # btrfs-image -r <tmp_file1> <tmp_file2>
>>>> # mount <tmp_file2> <mnt>
>>>>
>>>> This will dump all metadata from <RBD_DEV> to <tmp_file1>,
>>>> and then use <tmp_file1> to rebuild a image called <tmp_file2>.
>>>>
>>>> If <tmp_file2> can be mounted, then the metadata in the RBD device is
>>>> completely OK, and we can make conclusion the problem is not caused by
>>>> btrfs.(maybe ceph?)
>>>>
>>>> BTW, all the commands are recommended to be executed on the device which
>>>> you
>>>> get the debug info from.
>>>> As it's a small and almost empty device, so commands execution should be
>>>> quite fast on it.
>>>>
>>>> Thanks,
>>>> Qu
>>>>
>>>>
>>>> 在 2015年06月13日 00:09, Steve Dainard 写道:
>>>>>
>>>>>
>>>>> Hi Qu,
>>>>>
>>>>> I have another volume with the same error, btrfs-debug-tree output
>>>>> from btrfs-progs 4.0.1 is here: http://pastebin.com/k3R3bngE
>>>>>
>>>>> I'm not sure how to interpret the output, but the exit status is 0 so
>>>>> it looks like btrfs doesn't think there's an issue with the file
>>>>> system.
>>>>>
>>>>> I get the same mount error with options ro,recovery.
>>>>>
>>>>> On Fri, Jun 12, 2015 at 12:23 AM, Qu Wenruo <quwenruo@cn.fujitsu.com>
>>>>> wrote:
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>> -------- Original Message  --------
>>>>>> Subject: Can't mount btrfs volume on rbd
>>>>>> From: Steve Dainard <sdainard@spd1.com>
>>>>>> To: <linux-btrfs@vger.kernel.org>
>>>>>> Date: 2015年06月11日 23:26
>>>>>>
>>>>>>> Hello,
>>>>>>>
>>>>>>> I'm getting an error when attempting to mount a volume on a host that
>>>>>>> was forceably powered off:
>>>>>>>
>>>>>>> # mount /dev/rbd4 climate-downscale-CMIP5/
>>>>>>> mount: mount /dev/rbd4 on /mnt/climate-downscale-CMIP5 failed: Stale
>>>>>>> file
>>>>>>> handle
>>>>>>>
>>>>>>> /var/log/messages:
>>>>>>> Jun 10 15:31:07 node1 kernel: rbd4: unknown partition table
>>>>>>>
>>>>>>> # parted /dev/rbd4 print
>>>>>>> Model: Unknown (unknown)
>>>>>>> Disk /dev/rbd4: 36.5TB
>>>>>>> Sector size (logical/physical): 512B/512B
>>>>>>> Partition Table: loop
>>>>>>> Disk Flags:
>>>>>>>
>>>>>>> Number  Start  End     Size    File system  Flags
>>>>>>>      1      0.00B  36.5TB  36.5TB  btrfs
>>>>>>>
>>>>>>> # btrfs check --repair /dev/rbd4
>>>>>>> enabling repair mode
>>>>>>> Checking filesystem on /dev/rbd4
>>>>>>> UUID: dfe6b0c8-2866-4318-abc2-e1e75c891a5e
>>>>>>> checking extents
>>>>>>> cmds-check.c:2274: check_owner_ref: Assertion `rec->is_root` failed.
>>>>>>> btrfs[0x4175cc]
>>>>>>> btrfs[0x41b873]
>>>>>>> btrfs[0x41c3fe]
>>>>>>> btrfs[0x41dc1d]
>>>>>>> btrfs[0x406922]
>>>>>>>
>>>>>>>
>>>>>>> OS: CentOS 7.1
>>>>>>> btrfs-progs: 3.16.2
>>>>>>
>>>>>>
>>>>>>
>>>>>> The btrfs-progs seems quite old, and the above btrfsck error seems
>>>>>> quite
>>>>>> possible related to the old version.
>>>>>>
>>>>>> Would you please upgrade btrfs-progs to 4.0 and see what will happen?
>>>>>> Hopes it can give better info.
>>>>>>
>>>>>> BTW, it's a good idea to call btrfs-debug-tree /dev/rbd4 to see the
>>>>>> output.
>>>>>>
>>>>>> Thanks
>>>>>> Qu.
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>> Ceph: version: 0.94.1/CentOS 7.1
>>>>>>>
>>>>>>> I haven't found any references to 'stale file handle' on btrfs.
>>>>>>>
>>>>>>> The underlying block device is ceph rbd, so I've posted to both lists
>>>>>>> for any feedback. Also once I reformatted btrfs I didn't get a mount
>>>>>>> error.
>>>>>>>
>>>>>>> The btrfs volume has been reformatted so I won't be able to do much
>>>>>>> post mortem but I'm wondering if anyone has some insight.
>>>>>>>
>>>>>>> Thanks,
>>>>>>> Steve
>>>>>>> --
>>>>>>> To unsubscribe from this list: send the line "unsubscribe linux-btrfs"
>>>>>>> in
>>>>>>> the body of a message to majordomo@vger.kernel.org
>>>>>>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>>>>>>>
>>>>>>
>>>>
>>

Re: Can't mount btrfs volume on rbd

[Qu Wenruo]

Hi Steve,

I checked your binary dump.

Previously I was too focused on the assert error, but ignored some even 
larger bug...

As for the btrfs-debug-tree output, subvol 257 and 5 are completely 
corrupted.
Subvol 257 seems to contains a new tree root, and 5 seems to contains a 
new device tree.

------
fs tree key (FS_TREE ROOT_ITEM 0)
leaf 29409280 items 8 free space 15707 generation 9 owner 4
fs uuid 1bb22a03-bc25-466f-b078-c66c6f6a6d28
chunk uuid 11cca6df-e850-45d7-a928-cdff82c5f295
         item 0 key (0 DEV_STATS 1) itemoff 16243 itemsize 40
                 device stats
         item 1 key (1 DEV_EXTENT 0) itemoff 16195 itemsize 48
                 dev extent chunk_tree 3
                 chunk objectid 256 chunk offset 0 length 4194304
         item 2 key (1 DEV_EXTENT 4194304) itemoff 16147 itemsize 48
                 dev extent chunk_tree 3
                 chunk objectid 256 chunk offset 4194304 length 8388608
         item 3 key (1 DEV_EXTENT 12582912) itemoff 16099 itemsize 48
                 dev extent chunk_tree 3
......
# DEV_EXTENT should never occur in fs tree. It should only occurs in
# dev tree

file tree key (257 ROOT_ITEM 0)
leaf 29376512 items 13 free space 12844 generation 9 owner 1
fs uuid 1bb22a03-bc25-466f-b078-c66c6f6a6d28
chunk uuid 11cca6df-e850-45d7-a928-cdff82c5f295
         item 0 key (EXTENT_TREE ROOT_ITEM 0) itemoff 15844 itemsize 439
                 root data bytenr 29392896 level 0 dirid 0 refs 1 gen 9
                 uuid 00000000-0000-0000-0000-000000000000
         item 1 key (DEV_TREE ROOT_ITEM 0) itemoff 15405 itemsize 439
                 root data bytenr 29409280 level 0 dirid 0 refs 1 gen 9
                 uuid 00000000-0000-0000-0000-000000000000
         item 2 key (FS_TREE INODE_REF 6) itemoff 15388 itemsize 17
                 inode ref index 0 namelen 7 name: default
         item 3 key (FS_TREE ROOT_ITEM 0) itemoff 14949 itemsize 439
                 root data bytenr 29360128 level 0 dirid 256 refs 1 gen 4
                 uuid 00000000-0000-0000-0000-000000000000
         item 4 key (ROOT_TREE_DIR INODE_ITEM 0) itemoff 14789 itemsize 160
                 inode generation 3 transid 0 size 0 nbytes 16384
                 block group 0 mode 40755 links 1 uid 0 gid 0
                 rdev 0 flags 0x0
# These things are only in tree root.
------

So the problem is, the kernel you use has some bug (btrfs or rbd 
related), causing the btrfs write wrong tree blocks into existing tree 
blocks.

For such case, btrfsck won't be able to fix the critical error.
And I didn't even have an idea to fix the assert to change it into a 
normal error. As it's corrupting the whole structure of btrfs...

I can't even recall such critical btrfs bug...


Not familiar with rbd, but will it allow a block device to be mounted on 
different systems?

Like exporting a device A to system B and system C, and both system B 
and system C mounting device A at the same time as btrfs?

Thanks,
Qu

Qu Wenruo wrote on 2015/07/14 09:22 +0800:
> Thanks a lot Steve!
>
> With this binary dump, we can find out what's the cause of your problem
> and makes btrfsck handle and repair it.
>
> Further more, this provides a good hint on what's going wrong in kernel.
>
> I'll start investigating this right now.
>
> Thanks,
> Qu
>
> Steve Dainard wrote on 2015/07/13 13:22 -0700:
>> Hi Qu,
>>
>> I ran into this issue again, without pacemaker involved, so I'm really
>> not sure what is triggering this.
>>
>> There is no content at all on this disk, basically it was created with
>> a btrfs filesystem, mounted, and now after some reboots later (and
>> possibly hard resets) won't mount with a stale file handle error.
>>
>> I've DD'd the 10G disk and tarballed it to 10MB, I'll send it to you
>> in another email so the attachment doesn't spam the list.
>>
>> Thanks,
>> Steve
>>
>> On Mon, Jun 15, 2015 at 6:27 PM, Qu Wenruo <quwenruo@cn.fujitsu.com>
>> wrote:
>>>
>>>
>>> Steve Dainard wrote on 2015/06/15 09:19 -0700:
>>>>
>>>> Hi Qu,
>>>>
>>>> # btrfs --version
>>>> btrfs-progs v4.0.1
>>>> # btrfs check /dev/rbd30
>>>> Checking filesystem on /dev/rbd30
>>>> UUID: 1bb22a03-bc25-466f-b078-c66c6f6a6d28
>>>> checking extents
>>>> cmds-check.c:3735: check_owner_ref: Assertion `rec->is_root` failed.
>>>> btrfs[0x41aee6]
>>>> btrfs[0x423f5d]
>>>> btrfs[0x424c99]
>>>> btrfs[0x4258f6]
>>>> btrfs(cmd_check+0x14a3)[0x42893d]
>>>> btrfs(main+0x15d)[0x409c71]
>>>> /lib64/libc.so.6(__libc_start_main+0xf5)[0x7f29ce437af5]
>>>> btrfs[0x409829]
>>>>
>>>> # btrfs-image /dev/rbd30 rbd30.image -c9
>>>> # btrfs-image -r rbd30.image rbd30.image.2
>>>> # mount rbd30.image.2 temp
>>>> mount: mount /dev/loop0 on /mnt/temp failed: Stale file handle
>>>
>>> OK, my assumption are all wrong.
>>>
>>> I'd better check the debug-tree output more carefully.
>>>
>>> BTW, the rbd30 is the block device which you took the debug-tree output?
>>>
>>> If so, would you please do a dd dump of it and send it to me?
>>> If it contains important/secret info, just forget this.
>>>
>>> Maybe I can improve the btrfsck tool to fix it.
>>>
>>>>
>>>> I have a suspicion this was caused by pacemaker starting
>>>> ceph/filesystem resources on two nodes at the same time,I haven't
>>>> been able to replicate the issue after hard poweroff if ceph/btrfs are
>>>> not being controlled by pacemaker.
>>>
>>> Did you mean mount the same device on different system?
>>>
>>> Thanks,
>>> Qu
>>>
>>>>
>>>> Thanks for your help.
>>>>
>>>>
>>>>
>>>> On Mon, Jun 15, 2015 at 1:06 AM, Qu Wenruo <quwenruo@cn.fujitsu.com>
>>>> wrote:
>>>>>
>>>>> The debug result seems valid.
>>>>> So I'm afraid the problem is not in btrfs.
>>>>>
>>>>> Would your please try the following 2 things to eliminate btrfs
>>>>> problems?
>>>>>
>>>>> 1) btrfsck from 4.0.1 on the rbd
>>>>>
>>>>> If assert still happens, please update the image of the volume(dd
>>>>> image),
>>>>> to
>>>>> help us improve btrfs-progs.
>>>>>
>>>>> 2) btrfs-image dump and rebuilt the fs into other place.
>>>>>
>>>>> # btrfs-image <RBD_DEV> <tmp_file1> -c9
>>>>> # btrfs-image -r <tmp_file1> <tmp_file2>
>>>>> # mount <tmp_file2> <mnt>
>>>>>
>>>>> This will dump all metadata from <RBD_DEV> to <tmp_file1>,
>>>>> and then use <tmp_file1> to rebuild a image called <tmp_file2>.
>>>>>
>>>>> If <tmp_file2> can be mounted, then the metadata in the RBD device is
>>>>> completely OK, and we can make conclusion the problem is not caused by
>>>>> btrfs.(maybe ceph?)
>>>>>
>>>>> BTW, all the commands are recommended to be executed on the device
>>>>> which
>>>>> you
>>>>> get the debug info from.
>>>>> As it's a small and almost empty device, so commands execution
>>>>> should be
>>>>> quite fast on it.
>>>>>
>>>>> Thanks,
>>>>> Qu
>>>>>
>>>>>
>>>>> 在 2015年06月13日 00:09, Steve Dainard 写道:
>>>>>>
>>>>>>
>>>>>> Hi Qu,
>>>>>>
>>>>>> I have another volume with the same error, btrfs-debug-tree output
>>>>>> from btrfs-progs 4.0.1 is here: http://pastebin.com/k3R3bngE
>>>>>>
>>>>>> I'm not sure how to interpret the output, but the exit status is 0 so
>>>>>> it looks like btrfs doesn't think there's an issue with the file
>>>>>> system.
>>>>>>
>>>>>> I get the same mount error with options ro,recovery.
>>>>>>
>>>>>> On Fri, Jun 12, 2015 at 12:23 AM, Qu Wenruo <quwenruo@cn.fujitsu.com>
>>>>>> wrote:
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>> -------- Original Message  --------
>>>>>>> Subject: Can't mount btrfs volume on rbd
>>>>>>> From: Steve Dainard <sdainard@spd1.com>
>>>>>>> To: <linux-btrfs@vger.kernel.org>
>>>>>>> Date: 2015年06月11日 23:26
>>>>>>>
>>>>>>>> Hello,
>>>>>>>>
>>>>>>>> I'm getting an error when attempting to mount a volume on a host
>>>>>>>> that
>>>>>>>> was forceably powered off:
>>>>>>>>
>>>>>>>> # mount /dev/rbd4 climate-downscale-CMIP5/
>>>>>>>> mount: mount /dev/rbd4 on /mnt/climate-downscale-CMIP5 failed:
>>>>>>>> Stale
>>>>>>>> file
>>>>>>>> handle
>>>>>>>>
>>>>>>>> /var/log/messages:
>>>>>>>> Jun 10 15:31:07 node1 kernel: rbd4: unknown partition table
>>>>>>>>
>>>>>>>> # parted /dev/rbd4 print
>>>>>>>> Model: Unknown (unknown)
>>>>>>>> Disk /dev/rbd4: 36.5TB
>>>>>>>> Sector size (logical/physical): 512B/512B
>>>>>>>> Partition Table: loop
>>>>>>>> Disk Flags:
>>>>>>>>
>>>>>>>> Number  Start  End     Size    File system  Flags
>>>>>>>>      1      0.00B  36.5TB  36.5TB  btrfs
>>>>>>>>
>>>>>>>> # btrfs check --repair /dev/rbd4
>>>>>>>> enabling repair mode
>>>>>>>> Checking filesystem on /dev/rbd4
>>>>>>>> UUID: dfe6b0c8-2866-4318-abc2-e1e75c891a5e
>>>>>>>> checking extents
>>>>>>>> cmds-check.c:2274: check_owner_ref: Assertion `rec->is_root`
>>>>>>>> failed.
>>>>>>>> btrfs[0x4175cc]
>>>>>>>> btrfs[0x41b873]
>>>>>>>> btrfs[0x41c3fe]
>>>>>>>> btrfs[0x41dc1d]
>>>>>>>> btrfs[0x406922]
>>>>>>>>
>>>>>>>>
>>>>>>>> OS: CentOS 7.1
>>>>>>>> btrfs-progs: 3.16.2
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>> The btrfs-progs seems quite old, and the above btrfsck error seems
>>>>>>> quite
>>>>>>> possible related to the old version.
>>>>>>>
>>>>>>> Would you please upgrade btrfs-progs to 4.0 and see what will
>>>>>>> happen?
>>>>>>> Hopes it can give better info.
>>>>>>>
>>>>>>> BTW, it's a good idea to call btrfs-debug-tree /dev/rbd4 to see the
>>>>>>> output.
>>>>>>>
>>>>>>> Thanks
>>>>>>> Qu.
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>> Ceph: version: 0.94.1/CentOS 7.1
>>>>>>>>
>>>>>>>> I haven't found any references to 'stale file handle' on btrfs.
>>>>>>>>
>>>>>>>> The underlying block device is ceph rbd, so I've posted to both
>>>>>>>> lists
>>>>>>>> for any feedback. Also once I reformatted btrfs I didn't get a
>>>>>>>> mount
>>>>>>>> error.
>>>>>>>>
>>>>>>>> The btrfs volume has been reformatted so I won't be able to do much
>>>>>>>> post mortem but I'm wondering if anyone has some insight.
>>>>>>>>
>>>>>>>> Thanks,
>>>>>>>> Steve
>>>>>>>> --
>>>>>>>> To unsubscribe from this list: send the line "unsubscribe
>>>>>>>> linux-btrfs"
>>>>>>>> in
>>>>>>>> the body of a message to majordomo@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 majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html

Re: Can't mount btrfs volume on rbd

[Austin S Hemmelgarn]

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On 2015-07-21 04:38, Qu Wenruo wrote:
> Hi Steve,
>
> I checked your binary dump.
>
> Previously I was too focused on the assert error, but ignored some even
> larger bug...
>
> As for the btrfs-debug-tree output, subvol 257 and 5 are completely
> corrupted.
> Subvol 257 seems to contains a new tree root, and 5 seems to contains a
> new device tree.
>
> ------
> fs tree key (FS_TREE ROOT_ITEM 0)
> leaf 29409280 items 8 free space 15707 generation 9 owner 4
> fs uuid 1bb22a03-bc25-466f-b078-c66c6f6a6d28
> chunk uuid 11cca6df-e850-45d7-a928-cdff82c5f295
>          item 0 key (0 DEV_STATS 1) itemoff 16243 itemsize 40
>                  device stats
>          item 1 key (1 DEV_EXTENT 0) itemoff 16195 itemsize 48
>                  dev extent chunk_tree 3
>                  chunk objectid 256 chunk offset 0 length 4194304
>          item 2 key (1 DEV_EXTENT 4194304) itemoff 16147 itemsize 48
>                  dev extent chunk_tree 3
>                  chunk objectid 256 chunk offset 4194304 length 8388608
>          item 3 key (1 DEV_EXTENT 12582912) itemoff 16099 itemsize 48
>                  dev extent chunk_tree 3
> ......
> # DEV_EXTENT should never occur in fs tree. It should only occurs in
> # dev tree
>
> file tree key (257 ROOT_ITEM 0)
> leaf 29376512 items 13 free space 12844 generation 9 owner 1
> fs uuid 1bb22a03-bc25-466f-b078-c66c6f6a6d28
> chunk uuid 11cca6df-e850-45d7-a928-cdff82c5f295
>          item 0 key (EXTENT_TREE ROOT_ITEM 0) itemoff 15844 itemsize 439
>                  root data bytenr 29392896 level 0 dirid 0 refs 1 gen 9
>                  uuid 00000000-0000-0000-0000-000000000000
>          item 1 key (DEV_TREE ROOT_ITEM 0) itemoff 15405 itemsize 439
>                  root data bytenr 29409280 level 0 dirid 0 refs 1 gen 9
>                  uuid 00000000-0000-0000-0000-000000000000
>          item 2 key (FS_TREE INODE_REF 6) itemoff 15388 itemsize 17
>                  inode ref index 0 namelen 7 name: default
>          item 3 key (FS_TREE ROOT_ITEM 0) itemoff 14949 itemsize 439
>                  root data bytenr 29360128 level 0 dirid 256 refs 1 gen 4
>                  uuid 00000000-0000-0000-0000-000000000000
>          item 4 key (ROOT_TREE_DIR INODE_ITEM 0) itemoff 14789 itemsize 160
>                  inode generation 3 transid 0 size 0 nbytes 16384
>                  block group 0 mode 40755 links 1 uid 0 gid 0
>                  rdev 0 flags 0x0
> # These things are only in tree root.
> ------
>
> So the problem is, the kernel you use has some bug (btrfs or rbd
> related), causing the btrfs write wrong tree blocks into existing tree
> blocks.
>
> For such case, btrfsck won't be able to fix the critical error.
> And I didn't even have an idea to fix the assert to change it into a
> normal error. As it's corrupting the whole structure of btrfs...
>
> I can't even recall such critical btrfs bug...
>
>
> Not familiar with rbd, but will it allow a block device to be mounted on
> different systems?
>
> Like exporting a device A to system B and system C, and both system B
> and system C mounting device A at the same time as btrfs?
>
Yes, it's a distributed SAN type system built on top of Ceph.  It does 
allow having multiple systems mount the device.

Ideally, we really should put in some kind of protection against 
multiple mounts (this would be a significant selling point of BTRFS in 
my opinion, as the only other Linux native FS that has this is ext4), 
and make it _very_ obvious that mounting a BTRFS filesystem on multiple 
nodes concurrently _WILL_ result in pretty much irreparable corruption.


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Re: Can't mount btrfs volume on rbd

[Steve Dainard]

On Tue, Jul 21, 2015 at 4:15 AM, Austin S Hemmelgarn
<ahferroin7@gmail.com> wrote:
> On 2015-07-21 04:38, Qu Wenruo wrote:
>>
>> Hi Steve,
>>
>> I checked your binary dump.
>>
>> Previously I was too focused on the assert error, but ignored some even
>> larger bug...
>>
>> As for the btrfs-debug-tree output, subvol 257 and 5 are completely
>> corrupted.
>> Subvol 257 seems to contains a new tree root, and 5 seems to contains a
>> new device tree.
>>
>> ------
>> fs tree key (FS_TREE ROOT_ITEM 0)
>> leaf 29409280 items 8 free space 15707 generation 9 owner 4
>> fs uuid 1bb22a03-bc25-466f-b078-c66c6f6a6d28
>> chunk uuid 11cca6df-e850-45d7-a928-cdff82c5f295
>>          item 0 key (0 DEV_STATS 1) itemoff 16243 itemsize 40
>>                  device stats
>>          item 1 key (1 DEV_EXTENT 0) itemoff 16195 itemsize 48
>>                  dev extent chunk_tree 3
>>                  chunk objectid 256 chunk offset 0 length 4194304
>>          item 2 key (1 DEV_EXTENT 4194304) itemoff 16147 itemsize 48
>>                  dev extent chunk_tree 3
>>                  chunk objectid 256 chunk offset 4194304 length 8388608
>>          item 3 key (1 DEV_EXTENT 12582912) itemoff 16099 itemsize 48
>>                  dev extent chunk_tree 3
>> ......
>> # DEV_EXTENT should never occur in fs tree. It should only occurs in
>> # dev tree
>>
>> file tree key (257 ROOT_ITEM 0)
>> leaf 29376512 items 13 free space 12844 generation 9 owner 1
>> fs uuid 1bb22a03-bc25-466f-b078-c66c6f6a6d28
>> chunk uuid 11cca6df-e850-45d7-a928-cdff82c5f295
>>          item 0 key (EXTENT_TREE ROOT_ITEM 0) itemoff 15844 itemsize 439
>>                  root data bytenr 29392896 level 0 dirid 0 refs 1 gen 9
>>                  uuid 00000000-0000-0000-0000-000000000000
>>          item 1 key (DEV_TREE ROOT_ITEM 0) itemoff 15405 itemsize 439
>>                  root data bytenr 29409280 level 0 dirid 0 refs 1 gen 9
>>                  uuid 00000000-0000-0000-0000-000000000000
>>          item 2 key (FS_TREE INODE_REF 6) itemoff 15388 itemsize 17
>>                  inode ref index 0 namelen 7 name: default
>>          item 3 key (FS_TREE ROOT_ITEM 0) itemoff 14949 itemsize 439
>>                  root data bytenr 29360128 level 0 dirid 256 refs 1 gen 4
>>                  uuid 00000000-0000-0000-0000-000000000000
>>          item 4 key (ROOT_TREE_DIR INODE_ITEM 0) itemoff 14789 itemsize
>> 160
>>                  inode generation 3 transid 0 size 0 nbytes 16384
>>                  block group 0 mode 40755 links 1 uid 0 gid 0
>>                  rdev 0 flags 0x0
>> # These things are only in tree root.
>> ------
>>
>> So the problem is, the kernel you use has some bug (btrfs or rbd
>> related), causing the btrfs write wrong tree blocks into existing tree
>> blocks.
>>
>> For such case, btrfsck won't be able to fix the critical error.
>> And I didn't even have an idea to fix the assert to change it into a
>> normal error. As it's corrupting the whole structure of btrfs...
>>
>> I can't even recall such critical btrfs bug...
>>
>>
>> Not familiar with rbd, but will it allow a block device to be mounted on
>> different systems?
>>
>> Like exporting a device A to system B and system C, and both system B
>> and system C mounting device A at the same time as btrfs?
>>
> Yes, it's a distributed SAN type system built on top of Ceph.  It does allow
> having multiple systems mount the device.

This is accurate, but its a configured setting with the default being
not shareable. The host which has mapped the block device should have
a lock on it, so if another host attempts to map the same block device
it should error out.

The first time I had this occur was when it appeared pacemaker (HA
daemon) couldn't fence one of two nodes, and somehow bypassed the ceph
locking mechanism, mapping/mounting the block device on both nodes at
the same time which would account for corruption.

The last time this occurred (which is where the image you've analysed
came from) pacemaker was not involved, and only one node was
mapping/mounting the block device.

>
> Ideally, we really should put in some kind of protection against multiple
> mounts (this would be a significant selling point of BTRFS in my opinion, as
> the only other Linux native FS that has this is ext4), and make it _very_
> obvious that mounting a BTRFS filesystem on multiple nodes concurrently
> _WILL_ result in pretty much irreparable corruption.
>


I don't know if this has any bearing on the failure case, but the
filesystem that I sent an image of was only ever created, subvol
created, and mounted/unmounted several times. There was never any data
written to that mount point.

Re: Can't mount btrfs volume on rbd

[Qu Wenruo]

Steve Dainard wrote on 2015/07/21 14:07 -0700:
> On Tue, Jul 21, 2015 at 4:15 AM, Austin S Hemmelgarn
> <ahferroin7@gmail.com> wrote:
>> On 2015-07-21 04:38, Qu Wenruo wrote:
>>>
>>> Hi Steve,
>>>
>>> I checked your binary dump.
>>>
>>> Previously I was too focused on the assert error, but ignored some even
>>> larger bug...
>>>
>>> As for the btrfs-debug-tree output, subvol 257 and 5 are completely
>>> corrupted.
>>> Subvol 257 seems to contains a new tree root, and 5 seems to contains a
>>> new device tree.
>>>
>>> ------
>>> fs tree key (FS_TREE ROOT_ITEM 0)
>>> leaf 29409280 items 8 free space 15707 generation 9 owner 4
>>> fs uuid 1bb22a03-bc25-466f-b078-c66c6f6a6d28
>>> chunk uuid 11cca6df-e850-45d7-a928-cdff82c5f295
>>>           item 0 key (0 DEV_STATS 1) itemoff 16243 itemsize 40
>>>                   device stats
>>>           item 1 key (1 DEV_EXTENT 0) itemoff 16195 itemsize 48
>>>                   dev extent chunk_tree 3
>>>                   chunk objectid 256 chunk offset 0 length 4194304
>>>           item 2 key (1 DEV_EXTENT 4194304) itemoff 16147 itemsize 48
>>>                   dev extent chunk_tree 3
>>>                   chunk objectid 256 chunk offset 4194304 length 8388608
>>>           item 3 key (1 DEV_EXTENT 12582912) itemoff 16099 itemsize 48
>>>                   dev extent chunk_tree 3
>>> ......
>>> # DEV_EXTENT should never occur in fs tree. It should only occurs in
>>> # dev tree
>>>
>>> file tree key (257 ROOT_ITEM 0)
>>> leaf 29376512 items 13 free space 12844 generation 9 owner 1
>>> fs uuid 1bb22a03-bc25-466f-b078-c66c6f6a6d28
>>> chunk uuid 11cca6df-e850-45d7-a928-cdff82c5f295
>>>           item 0 key (EXTENT_TREE ROOT_ITEM 0) itemoff 15844 itemsize 439
>>>                   root data bytenr 29392896 level 0 dirid 0 refs 1 gen 9
>>>                   uuid 00000000-0000-0000-0000-000000000000
>>>           item 1 key (DEV_TREE ROOT_ITEM 0) itemoff 15405 itemsize 439
>>>                   root data bytenr 29409280 level 0 dirid 0 refs 1 gen 9
>>>                   uuid 00000000-0000-0000-0000-000000000000
>>>           item 2 key (FS_TREE INODE_REF 6) itemoff 15388 itemsize 17
>>>                   inode ref index 0 namelen 7 name: default
>>>           item 3 key (FS_TREE ROOT_ITEM 0) itemoff 14949 itemsize 439
>>>                   root data bytenr 29360128 level 0 dirid 256 refs 1 gen 4
>>>                   uuid 00000000-0000-0000-0000-000000000000
>>>           item 4 key (ROOT_TREE_DIR INODE_ITEM 0) itemoff 14789 itemsize
>>> 160
>>>                   inode generation 3 transid 0 size 0 nbytes 16384
>>>                   block group 0 mode 40755 links 1 uid 0 gid 0
>>>                   rdev 0 flags 0x0
>>> # These things are only in tree root.
>>> ------
>>>
>>> So the problem is, the kernel you use has some bug (btrfs or rbd
>>> related), causing the btrfs write wrong tree blocks into existing tree
>>> blocks.
>>>
>>> For such case, btrfsck won't be able to fix the critical error.
>>> And I didn't even have an idea to fix the assert to change it into a
>>> normal error. As it's corrupting the whole structure of btrfs...
>>>
>>> I can't even recall such critical btrfs bug...
>>>
>>>
>>> Not familiar with rbd, but will it allow a block device to be mounted on
>>> different systems?
>>>
>>> Like exporting a device A to system B and system C, and both system B
>>> and system C mounting device A at the same time as btrfs?
>>>
>> Yes, it's a distributed SAN type system built on top of Ceph.  It does allow
>> having multiple systems mount the device.
>
> This is accurate, but its a configured setting with the default being
> not shareable. The host which has mapped the block device should have
> a lock on it, so if another host attempts to map the same block device
> it should error out.
>
> The first time I had this occur was when it appeared pacemaker (HA
> daemon) couldn't fence one of two nodes, and somehow bypassed the ceph
> locking mechanism, mapping/mounting the block device on both nodes at
> the same time which would account for corruption.
>
> The last time this occurred (which is where the image you've analysed
> came from) pacemaker was not involved, and only one node was
> mapping/mounting the block device.
>
>>
>> Ideally, we really should put in some kind of protection against multiple
>> mounts (this would be a significant selling point of BTRFS in my opinion, as
>> the only other Linux native FS that has this is ext4), and make it _very_
>> obvious that mounting a BTRFS filesystem on multiple nodes concurrently
>> _WILL_ result in pretty much irreparable corruption.
>>
>
>
> I don't know if this has any bearing on the failure case, but the
> filesystem that I sent an image of was only ever created, subvol
> created, and mounted/unmounted several times. There was never any data
> written to that mount point.
>
Subvol creation and rw mount is enough to trigger 2~3 transaction with 
DATA written into btrfs.
As the first rw mount will create free space cache, which is counted as 
data.

But without multiple mount instants, I really can't consider another 
method to destroy btrfs so badly but with all csum OK...

Thanks,
Qu

Re: Can't mount btrfs volume on rbd

[Austin S Hemmelgarn]

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On 2015-07-21 22:01, Qu Wenruo wrote:
> Steve Dainard wrote on 2015/07/21 14:07 -0700:
>> I don't know if this has any bearing on the failure case, but the
>> filesystem that I sent an image of was only ever created, subvol
>> created, and mounted/unmounted several times. There was never any data
>> written to that mount point.
>>
> Subvol creation and rw mount is enough to trigger 2~3 transaction with
> DATA written into btrfs.
> As the first rw mount will create free space cache, which is counted as
> data.
>
> But without multiple mount instants, I really can't consider another
> method to destroy btrfs so badly but with all csum OK...
>
I know that a while back RBD had some intermittent issues with data 
corruption in the default configuration when the network isn't 
absolutely 100% reliable between all nodes (which for ceph means not 
only no packet loss, but also tight time synchronization between nodes 
and only very low network latency).

I also heard somewhere (can't remember exactly where though) of people 
having issues with ZFS on top of RBD.

The other thing to keep in mind is that Ceph does automatic background 
data scrubbing (including rewriting stuff it thinks is corrupted), so 
there is no guarantee that the data on the block device won't change 
suddenly without the FS on it doing anything.



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Re: Can't mount btrfs volume on rbd

[Gregory Farnum]

On Wed, Jul 22, 2015 at 12:16 PM, Austin S Hemmelgarn
<ahferroin7@gmail.com> wrote:
> On 2015-07-21 22:01, Qu Wenruo wrote:
>>
>> Steve Dainard wrote on 2015/07/21 14:07 -0700:
>>>
>>> I don't know if this has any bearing on the failure case, but the
>>> filesystem that I sent an image of was only ever created, subvol
>>> created, and mounted/unmounted several times. There was never any data
>>> written to that mount point.
>>>
>> Subvol creation and rw mount is enough to trigger 2~3 transaction with
>> DATA written into btrfs.
>> As the first rw mount will create free space cache, which is counted as
>> data.
>>
>> But without multiple mount instants, I really can't consider another
>> method to destroy btrfs so badly but with all csum OK...
>>
> I know that a while back RBD had some intermittent issues with data
> corruption in the default configuration when the network isn't absolutely
> 100% reliable between all nodes (which for ceph means not only no packet
> loss, but also tight time synchronization between nodes and only very low
> network latency).
>
> I also heard somewhere (can't remember exactly where though) of people
> having issues with ZFS on top of RBD.
>
> The other thing to keep in mind is that Ceph does automatic background data
> scrubbing (including rewriting stuff it thinks is corrupted), so there is no
> guarantee that the data on the block device won't change suddenly without
> the FS on it doing anything.

Ceph will automatically detect inconsistent data with its scrubbing,
but it won't rewrite that data unless the operator runs a repair
command. No invisible data changes! :)

I'm also not familiar with any consistency issues around network speed
or time sync, but I could have missed something. The only corruption
case I can think of was a release that enabled some local FS features
which in combination were buggy on some common kernels in the wild.
-Greg

Re: Can't mount btrfs volume on rbd

[Austin S Hemmelgarn]

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On 2015-07-22 10:13, Gregory Farnum wrote:
> On Wed, Jul 22, 2015 at 12:16 PM, Austin S Hemmelgarn
> <ahferroin7@gmail.com> wrote:
>> On 2015-07-21 22:01, Qu Wenruo wrote:
>>>
>>> Steve Dainard wrote on 2015/07/21 14:07 -0700:
>>>>
>>>> I don't know if this has any bearing on the failure case, but the
>>>> filesystem that I sent an image of was only ever created, subvol
>>>> created, and mounted/unmounted several times. There was never any data
>>>> written to that mount point.
>>>>
>>> Subvol creation and rw mount is enough to trigger 2~3 transaction with
>>> DATA written into btrfs.
>>> As the first rw mount will create free space cache, which is counted as
>>> data.
>>>
>>> But without multiple mount instants, I really can't consider another
>>> method to destroy btrfs so badly but with all csum OK...
>>>
>> I know that a while back RBD had some intermittent issues with data
>> corruption in the default configuration when the network isn't absolutely
>> 100% reliable between all nodes (which for ceph means not only no packet
>> loss, but also tight time synchronization between nodes and only very low
>> network latency).
>>
>> I also heard somewhere (can't remember exactly where though) of people
>> having issues with ZFS on top of RBD.
>>
>> The other thing to keep in mind is that Ceph does automatic background data
>> scrubbing (including rewriting stuff it thinks is corrupted), so there is no
>> guarantee that the data on the block device won't change suddenly without
>> the FS on it doing anything.
>
> Ceph will automatically detect inconsistent data with its scrubbing,
> but it won't rewrite that data unless the operator runs a repair
> command. No invisible data changes! :)
Ah, you're right, I forgot about needing admin intervention for changes 
(It's been a while since I tried to do anything with Ceph).
>
> I'm also not familiar with any consistency issues around network speed
> or time sync, but I could have missed something. The only corruption
> case I can think of was a release that enabled some local FS features
> which in combination were buggy on some common kernels in the wild.
Poor time synchronization between the nodes can cause some of the 
monitor nodes to lose their minds, which can cause corruption if the 
cluster is actually being utilized, but won't usually cause issues 
otherwise (although it will complain very noisily and persistently about 
lack of proper time synchronization).



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