Bug in qubes-backup or tar?

[svenss...@gmail.com]

Emergency recovery of backups as described in https://www.qubes-os.org/doc/backup-emergency-restore-v3/ states that tar should be able to unpack a qubes backup file.

It seems that qvm-backup produces a corrupt tar file, or the included tar has a bug. It seems to include data, but only one file will show up in list or extract.

My system is a recently updated 3.2.

# To reproduce, run in dom0:
qvm-create -t fedora-23 -l red test-bu
qvm-start test-bu
qvm-run test-bu 'echo "This text should be included in backup." > examplefile'
qvm-run -p test-bu 'ls -l e*; cat examplefile'
# Shows file and text
qvm-run test-bu 'sudo shutdown 0'
mkdir bu
qvm-backup bu test-bu
# Choose 'y', empty passphrase
tar tvf bu/qubes-*
# Shows only backup-header, size 94 bytes, no other file.
# Extracting the tar file produces only backup-header.
# However, the tar file has size 563200 bytes.

[Connor Page]

qvm-backup has a different syntax and vms are excluded from rather than included in a backup.

[svenss...@gmail.com]

On Saturday, June 17, 2017 at 11:36:29 AM UTC+2, Connor Page wrote:
> qvm-backup has a different syntax and vms are excluded from rather than included in a backup.

Well, it also lists the VMS that are about to be backed up, for confirmation. The test-bu VM was listed, and no other VMs.

Also, if the VM was not included in the backup, why is the backup file so much larger than what it supposedly contains?

[Rusty Bird]

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svenss...@gmail.com:

> Emergency recovery of backups as described in
> https://www.qubes-os.org/doc/backup-emergency-restore-v3/ states
> that tar should be able to unpack a qubes backup file.
>

> [...]

> tar tvf bu/qubes-*
> # Shows only backup-header, size 94 bytes, no other file.
> # Extracting the tar file produces only backup-header.
> # However, the tar file has size 563200 bytes.

The -i (--ignore-zeros) parameter is missing in the tar command.

Rusty
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[Axel Svensson]

The -i (--ignore-zeros) parameter is missing in the tar command.

So it is. Thank you!