The error message when a user supplies the wrong path information for the configuration file is misleading. It should say something like 'File not found' instead it misidentifies the missing file as a directory and directs the user to --help for further information.
- /usr/local/bin/mongod -f /etc/not-the-correct-name.conf
Error opening config file: Is a directory
try '/usr/local/bin/mongod --help' for more information