ntop products are bound to the system where they have been activated through a unique system identifier named systemId. This system identifier is computed based on the hardware configuration, including network devices.
If you are running a ntop product in a container (e.g. Docker), you probably want to activate it using the license generated for the host system, rather than generating a license for the specific container (which is also subject to change if you move it). In order to do this, the container requires visibility on the hardware configuration of the host, including network devices, this can be achieved configuring the container to use the host network namespace. In Docker you can do this with the –network=host option.
If you want to handle license installation and updates in a single place, you probably want to map also the license file from the host in the container. In Docker you can do this with -v /etc/<product>.license:/etc/<product>.license:ro
Example with nprobe running in a Docker container:
docker run -it --network=host -v /etc/nprobe.license:/etc/nprobe.license:ro nprobe
If you are still experiencing issues, it could be due to a more generic problem, please also read My license does not work: what can I do?
For more information about using ntop tools on Docker, please read more here.