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Container virtnbdmap command misses dependencies/requirements #282

@draggeta

Description

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Version used
Provide output of virtnbdbackup -V
2.34

Describe the bug
A clear and concise description of what the bug is.
When mounting backups using the virtnbdmap command, the following dependencies are missing:

  • nbdkit-plugin-python
  • nbdkit
  • nbd kernel module

Expected behavior
A clear and concise description of what you expected to happen.
The two packages (and maybe the modprobe nbd command) should be included in the container to allow it to run without issues.

Hypervisor and/or virtual machine information:

  • OS: Ubuntu 22.04
  • HV type: plain libvirt
  • Virtual machine configuration: None

Logfiles:
Please attach generated logfiles relevant to the reported issue.

admin@nc-backup:/opt/virtnbdbackup/app$ sudo docker run --rm -v /run:/run -v /var/tmp:/var/tmp -v /mnt/NFS/Backup:/mnt/NFS/Backup -v /opt/virtnbdbackup/config/ssh:/root/.ssh -v /dev:/dev --hostname nc-backup --network host ghcr.io/abbbi/virtnbdbackup virtnbdmap -f /mnt/NFS/Backup/hv01/server/2025-9/vda.full.data
[2025-09-26 08:58:06] INFO lib common - printVersion [main]:  Version: 2.34 Arguments: /usr/local/bin/virtnbdmap -f /mnt/NFS/Backup/hv01/server/2025-9/vda.full.data
[2025-09-26 08:58:06] INFO root virtnbdmap - main [main]:  Logfile: [/root/virtnbdmap.log]
[2025-09-26 08:58:06] INFO root virtnbdmap - main [main]:  Plugin location: [/usr/local/bin/virtnbd-nbdkit-plugin]
[2025-09-26 08:58:06] ERROR root requirements - executables [main]:  Please install required [nbdkit] utility.
[2025-09-26 08:58:06] ERROR root requirements - device [main]:  Target device [/dev/nbd0] does not exist, please load nbd module: [modprobe nbd]
admin@nc-backup:/opt/virtnbdbackup/app$ sudo modprobe nbd
admin@nc-backup:/opt/virtnbdbackup/app$ sudo docker run --rm -v /run:/run -v /var/tmp:/var/tmp -v /mnt/NFS/Backup:/mnt/NFS/Backup -v /opt/virtnbdbackup/config/ssh:/root/.ssh -v /dev:/dev --hostname nc-backup --network host ghcr.io/abbbi/virtnbdbackup virtnbdmap -f /mnt/NFS/Backup/hv01/server/2025-9/vda.full.data
[2025-09-26 08:58:26] INFO lib common - printVersion [main]:  Version: 2.34 Arguments: /usr/local/bin/virtnbdmap -f /mnt/NFS/Backup/hv01/server/2025-9/vda.full.data
[2025-09-26 08:58:26] INFO root virtnbdmap - main [main]:  Logfile: [/root/virtnbdmap.log]
[2025-09-26 08:58:26] INFO root virtnbdmap - main [main]:  Plugin location: [/usr/local/bin/virtnbd-nbdkit-plugin]
[2025-09-26 08:58:26] ERROR root requirements - executables [main]:  Please install required [nbdkit] utility.

admin@nc-backup:/opt/virtnbdbackup/app$ sudo docker run --rm -v /run:/run -v /var/tmp:/var/tmp -v /mnt/NFS/Backup:/mnt/NFS/Backup -v /opt/virtnbdbackup/config/ssh:/root/.ssh -v /dev:/dev --hostname nc-backup --network host ghcr.io/abbbi/virtnbdbackup /bin/bash -c "apt update && apt install -y nbdkit nbdkit-plugin-python && virtnbdmap -f /mnt/NFS/Backup/hv01/server/2025-9/vda.full.data"
# apt installs
[...]
Processing triggers for libc-bin (2.36-9+deb12u10) ...

[2025-09-26 09:05:08] INFO lib common - printVersion [main]:  Version: 2.34 Arguments: /usr/local/bin/virtnbdmap -f /mnt/NFS/Backup/hv01/server/2025-9/vda.full.data
[2025-09-26 09:05:08] INFO root virtnbdmap - main [main]:  Logfile: [/root/virtnbdmap.log]
[2025-09-26 09:05:08] INFO root virtnbdmap - main [main]:  Plugin location: [/usr/local/bin/virtnbd-nbdkit-plugin]
[2025-09-26 09:05:08] INFO root virtnbdmap - main [main]:  Write blockmap to temporary file: [/tmp/block.75juntvr.map]

Workaround:
Share possible workarounds, if any.
run the command with the following:

/bin/bash -c "sudo modprobe  nbd && apt update && apt install -y nbdkit nbdkit-plugin-python && virtnbdmap -f /mnt/NFS/Backup/hv01/server/2025-9/vda.full.data"

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