Docker container with external config has many permission problems

[Misterblue]

Since the built Docker image has an internal account of 'opensim' that runs the image and this account is 1000,1000, when external configuration directories are mounted, permissions are wrong (the Docker container tries to access the external files as 1000,1000 which is not the UID of the account that owns the external configuration files).
Consider creating the internal account with an odd UID (like 4444,4444) so an account can be created externally for the permissions. Maybe the internal account could be in a standard group?
An alternative is to change configuration building so it happens before the image is run. That is, all the setup scripts are run to update the configuration files so the container just needs to read them.