Re: How to change/fix 'Received UUID'

[Andrei Borzenkov <arvidjaar@gmail.com>]

08.03.2018 19:02, Marc MERLIN пишет:
> On Thu, Mar 08, 2018 at 09:34:45AM +0300, Andrei Borzenkov wrote:
>> 08.03.2018 09:06, Marc MERLIN пишет:
>>> On Tue, Mar 06, 2018 at 12:02:47PM -0800, Marc MERLIN wrote:
>>>>> https://github.com/knorrie/python-btrfs/commit/1ace623f95300ecf581b1182780fd6432a46b24d
>>>>
>>>> Well, I had never heard about it until now, thank you.
>>>>
>>>> I'll see if I can make it work when I get a bit of time.
>>>
>>> Sorry, I missed the fact that there was no code to write at all.
>>> gargamel:/var/local/src/python-btrfs/examples# ./set_received_uuid.py 2afc7a5e-107f-d54b-8929-197b80b70828 31337 1234.5678 /mnt/btrfs_bigbackup/DS1/Video_ro.20180220_21:03:41
>>> Current subvolume information:
>>>   subvol_id: 94887
>>>   received_uuid: 00000000-0000-0000-0000-000000000000
>>>   stime: 0.0 (1970-01-01T00:00:00)
>>>   stransid: 0  
>>>   rtime: 0.0 (1970-01-01T00:00:00)
>>>   rtransid: 0  
>>>
>>> Setting received subvolume...
>>>
>>> Resulting subvolume information:
>>>   subvol_id: 94887
>>>   received_uuid: 2afc7a5e-107f-d54b-8929-197b80b70828
>>>   stime: 1234.5678 (1970-01-01T00:20:34.567800)
>>>   stransid: 31337
>>>   rtime: 1520488877.415709329 (2018-03-08T06:01:17.415709)
>>>   rtransid: 255755
>>>
>>> gargamel:/var/local/src/python-btrfs/examples# btrfs property set -ts /mnt/btrfs_bigbackup/DS1/Video_ro.20180220_21:03:41 ro true
>>>
>>>
>>> ABORT: btrfs send -p /mnt/btrfs_pool1/Video_ro.20180205_21:05:15 Video_ro.20180307_22:03:03 |  btrfs receive /mnt/btrfs_bigbackup/DS1//. failed
>>> At subvol Video_ro.20180307_22:03:03
>>> At snapshot Video_ro.20180307_22:03:03
>>> ERROR: cannot find parent subvolume
>>>
>>> gargamel:/mnt/btrfs_pool1# btrfs subvolume show /mnt/btrfs_pool1/Video_ro.20180220_21\:03\:41/
>>> Video_ro.20180220_21:03:41
>>
>> Not sure I understand how this subvolume is related. You send
>> differences between Video_ro.20180205_21:05:15 and
>> Video_ro.20180307_22:03:03, so you need to have (replica of)
>> Video_ro.20180205_21:05:15 on destination. How exactly
>> Video_ro.20180220_21:03:41 comes in picture here?
>  
> Sorry, I pasted the wrong thing.
> ABORT: btrfs send -p /mnt/btrfs_pool1/Video_ro.20180220_21:03:41 Video_ro.20180308_07:50:06 |  btrfs receive /mnt/btrfs_bigbackup/DS1//. failed
> At subvol Video_ro.20180308_07:50:06
> At snapshot Video_ro.20180308_07:50:06
> ERROR: cannot find parent subvolume
> 
> Same problem basically, just copied the wrong attempt, sorry about that.
> 
> Do I need to make sure of more than
> DS1/Video_ro.20180220_21:03:41
> Received UUID:          2afc7a5e-107f-d54b-8929-197b80b70828
> 
> be equal to
> Name:                   Video_ro.20180220_21:03:41
> UUID:                   2afc7a5e-107f-d54b-8929-197b80b70828
> 

Yes. Your source has Received UUID. In this case btrfs send will
transmit received UUID instead of subvolume UUID as reference to base
snapshot. You need to either clear received UUID on source or set
received UUID on destination to received UUID of source (not to
subvolume UUID of source).

> Thanks,
> Marc
> 
> 
>>>         Name:                   Video_ro.20180220_21:03:41
>>>         UUID:                   2afc7a5e-107f-d54b-8929-197b80b70828
>>>         Parent UUID:            e5ec5c1e-6b49-084e-8820-5a8cfaa1b089
>>>         Received UUID:          0e220a4f-6426-4745-8399-0da0084f8b23
I mean this:                        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

>>>         Creation time:          2018-02-20 21:03:42 -0800
>>>         Subvolume ID:           11228
>>>         Generation:             4174
>>>         Gen at creation:        4150
>>>         Parent ID:              5
>>>         Top level ID:           5
>>>         Flags:                  readonly
>>>         Snapshot(s):
>>>                                 Video_rw.20180220_21:03:41
>>>                                 Video
>>>
>>>
>>> Wasn't I supposed to set 2afc7a5e-107f-d54b-8929-197b80b70828 onto the destination?
>>>
>>> Doesn't that look ok now? Is there something else I'm missing?
>>> gargamel:/mnt/btrfs_pool1# btrfs subvolume show /mnt/btrfs_bigbackup/DS1/Video_ro.20180220_21:03:41
>>> DS1/Video_ro.20180220_21:03:41
>>>         Name:                   Video_ro.20180220_21:03:41
>>>         UUID:                   cb4f343c-5e79-7f49-adf0-7ce0b29f23b3
>>>         Parent UUID:            0e220a4f-6426-4745-8399-0da0084f8b23
>>>         Received UUID:          2afc7a5e-107f-d54b-8929-197b80b70828
>>>         Creation time:          2018-02-20 21:13:36 -0800
>>>         Subvolume ID:           94887
>>>         Generation:             250689
>>>         Gen at creation:        250689
>>>         Parent ID:              89160
>>>         Top level ID:           89160
>>>         Flags:                  readonly
>>>         Snapshot(s):
>>>
>>> Thanks,
>>> Marc
>>>
>>
>>
>