Error message in browser - "The host header sent by the client is not allowed"

Hello, I’m a first-time user of Duplicati.

I figured I would try to run it on one of my Raspberry Pi 3 B+ devices under a Docker container, for ease of portability. I’m planning to set up Duplicati with Backblaze for encrypted backups.

When I ran the Docker container, using the command line below, and opened the Duplicati endpoint in Google Chrome (running on Windows 10), I received the error message below.

“The host header sent by the client is not allowed”

docker run -p 8200:8200 -v $(pwd)/duplicati:/app/duplicati duplicati/duplicati:linux-arm32v7-latest

Is there an environment variable that I need to set in the docker run command that maybe I’m missing? For now I just used the docker run command from the documentation on Docker Hub.

Yeah this is caused by additions to Duplicati to help protect against DNS-based attacks.

Try accessing the Duplicati UI using its IP address instead of a hostname. You can add the hostname to the appropriate area of the settings section to enable access by hostname.

More info here:

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