We know that when a new hard drive inserted to a mac, OSX will mount all partitions in it. In some situation, we may not want to mount some partitions. In that case, we need to adjust fstab manually.
Skills need:
1 OSX simply operations, and
2 vi operations.
Step:
1 mount the partitions / disks in question. If you want to adjust more than one, do them all at the same time or make them into several batches as you wish.
2 Remember the names or Universal Unique Identifiers of partitions. You can see the names as the text of the specific tree nodes within the left panel of Disk Utility. Universal Unique Identifiers can be found in the pop-up window shown after click the Info button. You can choose to remember names or Universal Unique Identifiers. If you choose to use name, all partitions with the same name will be affected in the same way.
3 Unmount the partitions / disks.
4 Open Terminal.
5 sudo -s
6 vi /etc/fstab
add lines one by one like this (choose one format below):
LABEL=name none ntfs ro,noauto 0 0
UUID=51C9C66D-B850-3285-884E-D48B9F616809 none msdos ro,noauto 0 0
You can check http://en.wikipedia.org/wiki/Fstab for more detailed information.
Save that file.
Now these partitions will not be mounted unless you do it manually.