My default music directory, under my username, has a symlink to my music library on a separate drive.
My MPD player is set to scan the database on start. However, the music drive isn't immediately recognized. I have to click the music folder open, then go back to the player and update the database; then I have my music.
The drive is mounted, but unlike my OS drive, when I first click a folder on this drive it takes a fraction of a second for it to open (with the little symbol that shows it's searching).