application.properties, log4j2.xml and certificate folder will be copied to the host at first time.
DB schema will be created on first startup when /var/lib/mysql in the docker container is empty.
SPRING_DATASOURCE_URL environment variable overrides the spring.datasource.url in the application.properties.
In case of aggregated and coupled compose the system is accessing the database through an internal docker network.
The database can be accessed by the human operators via the exposed port and with the given credentials (MYSQL_USER, MYSQL_PASSWORD) if necessary.
DOMAIN_NAME environment variable overrides the domain.name in the application.properties.
SERVICE_REGISTRY_ADDRESS environment variable overrides the service.registry.address in the application.properties.
SERVICE_REGISTRY_PORT environment variable overrides the service.registry.port in the application.properties.
Do not use localhost or 127.0.0.1 to address the Arrowhead Core or Support systems! Use always the real IP address of the given host machine. Or alternatively you can use the 172.17.0.1 docker bridge gateway address, but only within the same host machine that runs the docker engine.
To change any environment variable requires to recreate the related container.
Recreating a system container always overrides the bind mounts, so the /config folder content will be set back to the defaults. Always make sure to backup your configuration before system container recreation.
Recreating a database container does not effect the named volumes, so the new container will use the same persistent database files.