To Disable Automount
Getting the UUID
The first thing you will need is the volume's UUID (universal unique identifier) number, which can be found by opening Disk Utility, selecting the volume of interest, and then pressing Command+I or clicking the blue information button in the Disk Utility toolbar. In the window that appears, locate and copy the UUID, which is a string of alphanumeric characters separated by dashes.
Making changes to
With the UUID, you can now create an
fstab entry for the volume that prevents it from mounting:
fstab file by running the following command (supply your password when prompted):
sudo pico /etc/fstab
Create a new line at the end of the file that looks like the following (note: replace "NUMBER" with the full UUID string you copied from Disk Utility):
UUID=NUMBER none hfs rw,noauto
Save the file by pressing Control+O, followed by Control+X to quit the editor.
Perform these steps for each volume you wish to prevent automatically mounting, then restart the system, and they should no longer automatically mount. If you need to mount the volumes, then you can open Disk Utility and select them followed by clicking the Mount button in the toolbar, and they should become available in the Finder.