Yes you need to change the fstab.
Its not hard though.
Make sure only root is logged in,
Copy your /home directory to the drive,
unmount,
then open up fstab change the mount point of /dev/hda3 to /home
reboot and that should do it.
I have 18GB box didicated only to linux. No windows.
I have a partition on my harddisk that is mounted, hda3, but is not utilized by linux for any file structure. A 2.9GB partition is mounted as /, and everything in my linux system is there, literally filling it up.
(I thought I set it up for /home, but I guess not...)
How can I mount, say, /home under the hda3? Do I have to muck with /etc/fstab? That seems logical, but I wanted to get some input as to what is the best way to go about using this 'dead' space.
Jerry
Yes you need to change the fstab.
Its not hard though.
Make sure only root is logged in,
Copy your /home directory to the drive,
unmount,
then open up fstab change the mount point of /dev/hda3 to /home
reboot and that should do it.

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