tarExtract pipeline error: Invalid tar header

[nottheend]

Hopefully it will not appear with any storage anymore when this is implemented:

(9.0) Backup integrity - store size and checksum of backups. Also provide a way to "verify" backup integrity in the remote.

Mentioned in
what's coming in cloudron 9

[p44]

@nottheend ok thanks a lot

[p44]

Again, handling a "tarExtract pipeline error: incorrect header check" issue... on a different backup... very very sad for this... I hope you can release soon a solution because is risky to store backups that then cannot be restored @girish

[girish]

@p44 for encrypted backups, not sure what is the expected behaviour. If the backup is corrupt or password is forgotten, one cannot recover. What do you have in mind? What do you think Cloudron could have done? (or was your note about adding periodic integrity checks?)

[p44]

@girish

Periodic integrity checks – for example, verifying the backup archive and reporting issues proactively – could help discover corruption early, before a restore is needed. This would give admins a chance to re-run or fix backups in time.

What do you think about such a feature?

[p44]

Hi all, I'm still getting this error on Hetzner Storage Box:

"tarExtract pipeline error: invalid block type"

Even on a same backup did few minutes before, I had this error.
I moved away

[james]

Hello @p44
Could you please check the box.log and the backup log for error messages?
If you find something, please post this error message here.
I will try to investigate and with enough data I can even contact Hetzner directly, if the issue seems to be specific to Hetzner Storage Boxes.

[nottheend]

@james I had opened a ticket at that time with Hetzner. Sending you the ticket number as pm

[p44]

@james Thanks a lot, I found this:

2025-07-20T18:54:47.274Z box:tasks startTask: 1458 done. error: { stack: 'BoxError: tarExtract pipeline error: invalid block type\n' + '    at tarExtract (/home/yellowtent/box/src/backupformat/tgz.js:225:26)\n' + '    at process.processTicksAndRejections (node:internal/process/task_queues:95:5)\n' + '    at async /home/yellowtent/box/src/backupformat/tgz.js:248:9\n' + '    at async promiseRetry (/home/yellowtent/box/src/promise-retry.js:17:20)\n' + '    at async Object.download (/home/yellowtent/box/src/backupformat/tgz.js:244:5)\n' + '    at async download (/home/yellowtent/box/src/backuptask.js:104:5)\n' + '    at async Object.downloadApp (/home/yellowtent/box/src/backuptask.js:138:5)\n' + '    at async install (/home/yellowtent/box/src/apptask.js:368:9)', name: 'BoxError', reason: 'External Error', details: {}, message: 'tarExtract pipeline error: invalid block type' }

Other specific backup logs were rotated.

Maybe Hetzner do some kind of compression on the file, or manipulation? (https://stackoverflow.com/questions/76818505/why-is-the-disk-usage-on-the-hetzner-storage-box-less-than-on-the-hetzner-dedica)

Edit: I found also these posts that mentioned errors, the first one with .tar.gz:

• https://forum.rclone.org/t/files-corrupted-with-hetzner-storage-box/39016
• https://www.reddit.com/r/hetzner/comments/1ihlhhp/corrupted_files_in_storage_box_mounted_as_smb/

While we try to understand this better, I would suggest not using the Hetzner Storage Box as primary backup.

Edit2: @james keep us posted about directly contact with Hetzner.

[jdaviescoates]

@p44 said in tarExtract pipeline error: Invalid tar header:

While we try to understand this better, I would suggest not using the Hetzner Storage Box as primary backup.

Is this just when using encryption?

I don't use encryption, but I've been using Hetzner Storage Boxes for about 6.5 years now without issue so far, including a few complete server migrations with no issues.

[p44]

@jdaviescoates Yes, with encryption. Me too, I never had issues with Hetzner Storage Boxes but since few months various problem happens...