When starting the Keycloak instance you can pass a number of environment variables to configure how it connects to SQL Server. For example: docker run --name keycloak -e KEYCLOAK_LOGLEVEL=DEBUG -e ...
The mssql protocol logfile is missing output when using the --debug flag. There are missing INFO and DEBUG output in the logfile that are visible to stdout. [15:55:32] DEBUG NXC VERSION: 1.2.0 - ...