yes, because in order to do so, firefly has to be started successfully.
And in order to do that, the mp3_dir has to be accessible to mt-daapd.
So you have to edit the config file yourself, and then start mt-daapd.
The command to start it is:
To view any log outputs do:
tail -f /var/log/messages
without the -f it will just print the last 10 lines of that logfile, with -f it will follow the file and display any new output on screen.
To quit, simply press CTRL+C.