Error when trying to use Duplicati

I have no clue where I should ask for help, so I’m sorry if this is the wrong spot…

When running duplicati, I get this error:
The operation Repair has failed\nUserInformationException: The backup storage destination is missing data files. You can either enable `--rebuild-missing-dblock-files` or run the purge-broken-files command to remove these files. The following files are missing: duplicati-bc2c10498637a4286bf12762543ffb76a.dblock.zip.aes"

and I don’t know how to solve this (new to Zima OS).

Welcome Marcello

That error is not a ZimaOS issue, it’s coming directly from Duplicati.

What it means (in simple terms):

One of the backup block files (.dblock.zip.aes) is missing from your backup destination.
This usually happens if:

• The storage was manually modified
• A sync tool deleted files
• The disk had corruption
• The backup destination is incomplete


What you can do

You have two recovery options:

Option 1 – Rebuild missing block files (safest first try)

In Duplicati advanced options, add:

--rebuild-missing-dblock-files=true

Then run Repair again.

This attempts to recreate the missing index data from what still exists.


Option 2 – Purge broken files

If rebuild fails, run:

purge-broken-files

This removes references to missing backup blocks.
You may lose restore points that depended on that block.


Important questions

Before doing anything destructive:

  1. Is your backup destination local disk, USB, NAS, or cloud?
  2. Did you manually delete or move any files in the backup folder?
  3. Is the storage mounted correctly and fully accessible?

If this is on an external drive or network share, first confirm the full backup folder is present and not partially mounted.


If you post:

  • Where the backup is stored
  • How Duplicati is deployed (Docker or native)
  • A screenshot of the destination folder contents

We can guide you safely

duplicati is installed via app store, so I think it is a docker container.
I want to backup from a local disk (ssd1) to another local disk (hdd)
I found out that I had to choose something like
source: /source/media/SSD1TB/SSD1TB/MP3/
destination: /source/media/HDD-Storage/HDD/Monday/MP3/
(the destination exists already and is still empty, just created, so useless to have a screenshot)
I selected the above via the directory/file selector (not by manual)

Good, this is almost certainly a path mapping issue, not corruption.

Since you installed Duplicati from the ZimaOS App Store, it runs in Docker.
That means it can only see folders that are mounted into the container.

If the destination folder exists on the host but is not mounted inside the Duplicati container, Duplicati will think files are missing or incomplete.


What’s likely happening

You selected:

/source/media/SSD1TB/SSD1TB/MP3/
/source/media/HDD-Storage/HDD/Monday/MP3/

Those look like host paths.

Inside the container they may:

  • Not exist
  • Be partially mapped
  • Point to a different internal path

So Duplicati creates metadata, then cannot see it again → “missing dblock”.


Verify this (important)

Open terminal and run:

docker ps | grep duplicati

Copy the container name.

Then:

docker inspect <container_name> | grep -A5 Mounts

You need to confirm:

  • SSD source disk is mounted
  • HDD destination disk is mounted
  • The paths match what Duplicati sees

Most common mistake

ZimaOS mounts disks like:

/media/xxxx

But App Store containers often mount them internally as something like:

/data
/storage
/source

The internal path may NOT match the host path you selected.


Correct approach

  1. Open Duplicati
  2. Go to Backup > Edit > Destination
  3. Use the built-in folder browser
  4. Confirm you can browse and see files inside both disks
  5. Do NOT manually type host paths

Important question

When you browse inside Duplicati:

  • Do you actually see the HDD content?
  • Or does the folder appear empty/unreachable?

That will tell us immediately if it’s a mount problem.


Do NOT run purge or rebuild yet, this is very likely configuration, not damaged backup.

I’ve put a temp.txt file inside the destination folder, but the file browser doesn’t show that. I can test the destination “Connection tested successfully.“ I think this file browser only can show folders, because wherever I click, I can only see folders, no files inside.
So yes, the folder seems empty to duplicati (but not remote via samba)
(and I did select the folder with that file browser)

I don’t know how to do that terminal command, because I don’t see any terminal application :frowning:

Good, this confirms it.

Duplicati (Docker) cannot see your HDD mount.
Samba can see it, but the container cannot.

This is a volume mapping issue.


Fix (no terminal)

  1. ZimaOS → Apps
  2. Duplicati > ⋯ > Settings / Edit
  3. Find Volume / Directory Mapping

Make sure your HDD is mapped, e.g.:

Host:

/media/HDD-Storage

Container:

/backup

Save → restart container.

Then set destination in Duplicati to:

/backup/Monday/MP3

Do not use /source/media/...


If temp.txt isn’t visible inside Duplicati, the disk is simply not mounted into the container.

It seems to work now.
Can I add multiple sources, because not everything I want to backup is on the same drive?

Yes, you can add multiple source folders in one backup job in Duplicati.

But one rule:

Every source folder must be mounted into the Docker container, or Duplicati won’t see it.


What to do

  1. Edit your backup
  2. Go to Source Data
  3. Click Add folder
  4. Select additional paths

If a folder does not appear → it is not mapped in container settings.


If it’s on another disk

Go to:

ZimaOS > Apps > Duplicati > Settings
Add another volume mapping:

Host:

/media/OtherDisk

Container:

/data2

Restart container.

Then inside Duplicati you’ll see /data2.


You can back up as many folders and drives as you want, just ensure they are properly mounted into the container first.

Nice :slight_smile:
Thank you for helping me to set it up, much appreciated!!!

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