I'm currently getting sane about an issue in docker on openmediavault and I can't find any solution by myself.
Please allow me to describe the issue in some words: When creating docker container for the document management systems paperless-ng the webserver-container is unable to resolve the other containers. I tried to setup that stuff with docker compose, following the installation guide.
After creating the container with the docker-compose up -d command, the webserver-container states could not translate host name "db" to address: Temporary failure in name resolution and even the db-container is in state could not resolve "localhost": Temporary failure in name resolution.
It seems like my docker installation doesn't allow any dns-lookups at all for container in a bridge network and I have no idea why. Do anyone know about any incompatibility between portainer and docker-compose? Or does anyone have an idea where to dig into that issue? I'm googling around for a couple of days but unfortunately, I'm obviously not hitting the right search string...
I've had a comparable problem while testing a mayan edms docker instance: The instance was running fine but was unable to resolve the mayan-homepage for it's integrated update check mechanism. In the meanwhile my portainer and a watchtower instance are running fine on the system bridge network and at least watchtower is able to lookup hosts in the internet as it sends mail and pulls new images as it should.
Before I throw away my current setup and start with a clean install I'd like to send an SOS to the community: Has anyone an idea where to look for the root cause?