Error creating backup: unexpected end of data #134881

GitHobi · 2025-01-06T12:44:36Z

The problem

Creating manual or automated backups fails with the error message "Failed to create backup".

What version of Home Assistant Core has the issue?

2025.1.0

What was the last working version of Home Assistant Core?

No response

What type of installation are you running?

Home Assistant Container

Integration causing the issue

homeassistant.components.backup

Link to integration documentation on our website

No response

Diagnostics information

No response

Example YAML snippet

No response

Anything in the logs that might be useful for us?

2025-01-06 13:35:25.645 DEBUG (MainThread) [homeassistant.components.backup] Backup state: idle -> create_backup
2025-01-06 13:35:25.646 INFO (MainThread)  [homeassistant.components.recorder.backup] Backup start notification, locking database for writes
2025-01-06 13:35:25.646 DEBUG (MainThread) [homeassistant.components.recorder.core] Not a SQLite database or not connected, locking not necessary
2025-01-06 13:35:25.958 INFO (MainThread)  [homeassistant.components.recorder.backup] Backup end notification, releasing write lock
2025-01-06 13:35:25.958 DEBUG (MainThread) [homeassistant.components.recorder.core] Not a SQLite database or not connected, unlocking not necessary
2025-01-06 13:35:25.959 DEBUG (MainThread) [homeassistant.components.backup] Backup state: create_backup -> idle
2025-01-06 13:35:25.959 ERROR (MainThread) [homeassistant.components.backup] Error creating backup: unexpected end of data

Additional information

The backup is actually created - at least there are files generated in the backup-folder, but the UI does not show or list these files.
Tries already to remove the backup folder and restart - this regenerates the folder, but does not change anything.

home-assistant · 2025-01-06T19:33:27Z

Hey there @home-assistant/core, mind taking a look at this issue as it has been labeled with an integration (backup) you are listed as a code owner for? Thanks!

Code owner commands

Code owners of backup can trigger bot actions by commenting:

@home-assistant close Closes the issue.
@home-assistant rename Awesome new title Renames the issue.
@home-assistant reopen Reopen the issue.
@home-assistant unassign backup Removes the current integration label and assignees on the issue, add the integration domain after the command.
@home-assistant add-label needs-more-information Add a label (needs-more-information, problem in dependency, problem in custom component) to the issue.
@home-assistant remove-label needs-more-information Remove a label (needs-more-information, problem in dependency, problem in custom component) on the issue.

_{^{(message by CodeOwnersMention)}}

backup documentation
backup source
_{^{(message by IssueLinks)}}

MartinHjelmare · 2025-02-22T21:25:10Z

Please update to the latest Core version and try creating an automatic backup. You can do that from the GUI.

Please use the following logger integration YAML settings:

logger:
  default: warning
  logs:
    homeassistant.components.backup: debug
    homeassistant.components.hassio: debug

https://www.home-assistant.io/integrations/logger/

GitHobi · 2025-02-23T07:10:41Z

Hi - I've updated to 2025.2.5, logger configured as requested.

Tried to do a manual backup - failed.

Log says:

hass              | 2025-02-23 08:01:09.255 DEBUG (MainThread) [homeassistant.components.backup] Backup state: idle -> create_backup
hass              | 2025-02-23 08:01:09.330 DEBUG (SyncWorker_3) [homeassistant.components.backup] Ignoring data/backups/h2302-2_2025-02-23_07.59_26819824.tar because of backups/*.tar
hass              | 2025-02-23 08:01:09.330 DEBUG (SyncWorker_3) [homeassistant.components.backup] Ignoring data/backups/test_2025-02-23_08.01_09255979.tar because of backups/*.tar
hass              | 2025-02-23 08:01:09.695 DEBUG (MainThread) [homeassistant.components.backup] Backup state: create_backup -> idle
hass              | 2025-02-23 08:01:09.695 ERROR (MainThread) [homeassistant.components.backup] Error creating backup: unexpected end of data

Interesting so, it seems the backups are getting created, at least they seem to be in the backup folder:

root@hass:/opt/docker/homeassistant# ll data/backups/
total 672
drwxr-xr-x  2 root   4096 Feb 23 08:01 .
drwxr-xr-x 15 root   4096 Feb 23 07:58 ..
-rw-r--r--  1 root 337920 Feb 23 07:59 h2302-2_2025-02-23_07.59_26819824.tar
-rw-r--r--  1 root 337920 Feb 23 08:01 test_2025-02-23_08.01_09255979.tar

Also to mention: It requires a restart of HA to see these backups in the gui.

(did not test if these backups would work).

emontnemery · 2025-02-23T15:12:08Z

I think there might be some file in the data folder which can't be read when we create the backup.

GitHobi · 2025-02-23T15:14:50Z

Any chance to find out which file / folder this might be?
To what I can tell, all files / folders are globally readable.

emontnemery · 2025-02-26T08:25:38Z

PR #139273, which will be included in the Home Assistant Core beta 2025.3.0b0 scheduled for release today, improves logging of file I/O errors.

GitHobi · 2025-02-26T18:12:11Z

Many thanks - 2025.3.0b0 provided the information which file causes the issue.
I had a file "temp" (actually 0 bytes, readable for everyone) in the config folder - after deleting this file the backups worked without problems!

emontnemery · 2025-02-27T06:36:22Z

Many thanks - 2025.3.0b0 provided the information which file causes the issue. I had a file "temp" (actually 0 bytes, readable for everyone) in the config folder - after deleting this file the backups worked without problems!

I doubt it's that simple, empty files are generally not a problem. Do you by chance have a way to restore the offending file?

GitHobi · 2025-02-27T07:09:27Z

Yes I have ... I can give I try later this day.

GitHobi · 2025-02-27T18:00:26Z

I restored my configuration from a backup - which brought back the (actual) two files I had deleted yesterday:

-rwxr-xr-x  1 root      0 May 25  2023  temp
-rw-r--r--  1 root      0 Jun  7  2023  test.db

If I trigger a backup - without restarting the docker container - the backup works without problems.

After restarting the container, I get the same error message as I got before:

hass              | 2025-02-27 18:46:48.429 DEBUG (MainThread) [homeassistant.components.backup] Backup state: idle -> create_backup
hass              | 2025-02-27 18:46:48.510 DEBUG (SyncWorker_1) [homeassistant.components.backup] Ignoring data/backups/Automatic_backup_2025.3.0b0_2025-02-27_04.47_21001433.tar because of backups/*.tar
hass              | 2025-02-27 18:46:48.511 DEBUG (SyncWorker_1) [homeassistant.components.backup] Ignoring data/backups/m3_2025-02-27_18.40_12369869.tar because of backups/*.tar
hass              | 2025-02-27 18:46:48.511 DEBUG (SyncWorker_1) [homeassistant.components.backup] Ignoring data/backups/m4_2025-02-27_18.41_08036836.tar because of backups/*.tar
hass              | 2025-02-27 18:46:48.511 DEBUG (SyncWorker_1) [homeassistant.components.backup] Ignoring data/backups/m1_2025-02-27_18.33_13472001.tar because of backups/*.tar
hass              | 2025-02-27 18:46:48.512 DEBUG (SyncWorker_1) [homeassistant.components.backup] Ignoring data/backups/Custom_backup_2025.3.0b0_2025-02-27_18.46_48429443.tar because of backups/*.tar
hass              | 2025-02-27 18:46:48.512 DEBUG (SyncWorker_1) [homeassistant.components.backup] Ignoring data/backups/m2_2025-02-27_18.34_09524414.tar because of backups/*.tar
hass              | 2025-02-27 18:46:48.512 DEBUG (SyncWorker_1) [homeassistant.components.backup] Ignoring data/backups/Initial_Backup_2025-02-26_19.10_09030394.tar because of backups/*.tar
hass              | 2025-02-27 18:46:48.513 DEBUG (SyncWorker_1) [homeassistant.components.backup] Ignoring data/backups/jjjj_2025-02-26_19.06_31200438.tar because of backups/*.tar
hass              | 2025-02-27 18:46:48.881 DEBUG (MainThread) [homeassistant.components.backup] Backup state: create_backup -> idle
hass              | 2025-02-27 18:46:48.881 ERROR (MainThread) [homeassistant.components.backup] Unexpected error: Error adding /config/temp to tarfile: unexpected end of data (OSError)
hass              | Traceback (most recent call last):
hass              |   File "/usr/local/lib/python3.13/site-packages/securetar/__init__.py", line 616, in _atomic_contents_add
hass              |     tar_file.add(
hass              |     ~~~~~~~~~~~~^
hass              |         directory_item.as_posix(), arcname=item_arcname, recursive=False
hass              |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
hass              |     )
hass              |     ^
hass              |   File "/usr/local/lib/python3.13/tarfile.py", line 2241, in add
hass              |     self.addfile(tarinfo, f)
hass              |     ~~~~~~~~~~~~^^^^^^^^^^^^
hass              |   File "/usr/local/lib/python3.13/tarfile.py", line 2272, in addfile
hass              |     copyfileobj(fileobj, self.fileobj, tarinfo.size, bufsize=bufsize)
hass              |     ~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
hass              |   File "/usr/local/lib/python3.13/tarfile.py", line 258, in copyfileobj
hass              |     raise exception("unexpected end of data")
hass              | OSError: unexpected end of data
hass  
8000
            |
hass              | The above exception was the direct cause of the following exception:
hass              |
hass              | Traceback (most recent call last):
hass              |   File "/usr/src/homeassistant/homeassistant/components/backup/manager.py", line 1119, in _async_finish_backup
hass              |     written_backup = await self._backup_task
hass              |                      ^^^^^^^^^^^^^^^^^^^^^^^
hass              |   File "/usr/src/homeassistant/homeassistant/components/backup/manager.py", line 1563, in _async_create_backup
hass              |     tar_file_path, size_in_bytes = await self._hass.async_add_executor_job(
hass              |                                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
hass              |     ...<5 lines>...
hass              |     )
hass              |     ^
hass              |   File "/usr/local/lib/python3.13/concurrent/futures/thread.py", line 59, in run
hass              |     result = self.fn(*self.args, **self.kwargs)
hass              |   File "/usr/src/homeassistant/homeassistant/components/backup/manager.py", line 1661, in _mkdir_and_generate_backup_contents
hass              |     atomic_contents_add(
hass              |     ~~~~~~~~~~~~~~~~~~~^
hass              |         tar_file=core_tar,
hass              |         ^^^^^^^^^^^^^^^^^^
hass              |     ...<2 lines>...
hass              |         arcname="data",
hass              |         ^^^^^^^^^^^^^^^
hass              |     )
hass              |     ^
hass              |   File "/usr/local/lib/python3.13/site-packages/securetar/__init__.py", line 575, in atomic_contents_add
hass              |     return _atomic_contents_add(tar_file, origin_path, file_filter, arcname)
hass              |   File "/usr/local/lib/python3.13/site-packages/securetar/__init__.py", line 620, in _atomic_contents_add
hass              |     raise AddFileError(
hass              |     ...<5 lines>...
hass              |     ) from err
hass              | securetar.AddFileError: Error adding /config/temp to tarfile: unexpected end of data (OSError)

Backup fails almost immediately. A backup file is created (but only 310kb in size - instead 30 MB).

After removing this "temp" file, backup works again ...

emontnemery · 2025-02-28T09:05:39Z

If I trigger a backup - without restarting the docker container - the backup works without problems.
After restarting the container, I get the same error message as I got before

Does it mean that before you restart the container, the backup is successfully done, and it contains both the temp and the test.db files?

emontnemery · 2025-02-28T09:22:07Z

Can you try to check if anything has the temp file open, maybe via lsof?

GitHobi · 2025-02-28T16:09:11Z

ok. Did the test again.

- remove "temp" file.
- restart HA
- manual backup => works
- "touch temp"
- manual backup => fails.
- restart HA
- manual backup => fails.
goto 1 :)

The file does not seem to be open by any process, at least lsof / fsuser does not report anything.

Not sure whats going on here :)

emontnemery · 2025-03-02T08:03:12Z

OK, so as soon as the "temp" file is there, the backup fails to be created, it doesn't fail only after you restart the container?
I think that should make this issue easier to track down.

emontnemery · 2025-03-02T08:22:06Z

Please open a shell in the Home Assistant container and try the snippet below, then paste the output here.
I'm not sure if "/config/temp" is the correct path to the offending file inside the container, please adjust it as needed.

python3 --version
python3
>>> import pathlib
>>> print(pathlib.Path("/config/temp").stat())
>>> import tarfile
>>> with tarfile.open("test.tar", mode="w") as tf:
...    tf.add("/config/temp")
...

GitHobi · 2025-03-02T12:26:12Z

Aaaargh ... sorry, I guess its sort of a "layer 8 problem" :(
"temp" is actually a special file, I checked my compose file ... I'm mapping the temperature readig of the host into the container (to my excuse: it did this a long time ago ...)

volumes:
   - ./data/:/config
   - /sys/class/thermal/thermal_zone0/temp:/config/temp:ro

Seems that the backup process cannot process this "file".

/config # python3 --version
Python 3.13.2
/config # python3
Python 3.13.2 (main, Feb 14 2025, 12:18:52) [GCC 14.2.0] on linux
Type "help", "copyright", "credits" or "license" for more information.

import pathlib
print(pathlib.Path("/config/temp").stat())
os.stat_result(st_mode=33060, st_ino=10529, st_dev=18, st_nlink=1, st_uid=0, st_gid=0, st_size=4096, st_atime=1733503118, st_mtime=1733503118, st_ctime=1733503118)
import tarfile

with tarfile.open("test.tar", mode="w") as tf:
... tf.add("/config/temp")
...
Traceback (most recent call last):
File "", line 2, in
tf.add("/config/temp")
~~~~~~^^^^^^^^^^^^^^^^
File "/usr/local/lib/python3.13/tarfile.py", line 2241, in add
self.addfile(tarinfo, f)
~~~~~~~~~~~~^^^^^^^^^^^^
File "/usr/local/lib/python3.13/tarfile.py", line 2272, in addfile
copyfileobj(fileobj, self.fileobj, tarinfo.size, bufsize=bufsize)
~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/usr/local/lib/python3.13/tarfile.py", line 258, in copyfileobj
raise exception("unexpected end of data")
OSError: unexpected end of data

I guess I need to map the temperature reading somewhere outside of the "config" folder.

emontnemery · 2025-03-02T14:56:52Z

OK, I see. However, the Python tarfile library should not try to copy non regular files.
What's the type of the file, inside and outside of the container? Or is this somehow a special regular file?

Also, this should reveal what Python thinks:

python3
>>> import pathlib
>>> print(pathlib.Path("/config/temp").stat())
>>> import tarfile
>>> with tarfile.open("test.tar", mode="w") as tf:
...    info = tf.gettarinfo("/config/temp")
...    print(info.type)
...    print(info.isreg())
...

GitHobi · 2025-03-02T14:59:32Z

My "temp" file was actually /sys/class/thermal/thermal_zone0/temp ... I guess this counts as "special regular file".
I think the issue is solved - I take the blame on me :( :)

frenck added the integration: backup label Jan 6, 2025

MartinHjelmare changed the title ~~backups not working~~ Error creating backup: unexpected end of data Feb 3, 2025

MartinHjelmare added the needs-more-information label Feb 22, 2025

GitHobi closed this as completed Feb 26, 2025

MartinHjelmare removed the needs-more-information label Feb 26, 2025

emontnemery reopened this Feb 27, 2025

GitHobi closed this as completed Mar 2, 2025

github-actions bot locked and limited conversation to collaborators Apr 1, 2025

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

Uh oh!

Uh oh!

Error creating backup: unexpected end of data #134881

Error creating backup: unexpected end of data #134881

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Uh oh!