The simple way would be to run this command
That command will run through a list of messages about hardware added/initialized. From there all you will need to do is figure out which hard drive you are using, and if you have not partitioned it, you can use the graphical tool, you can simply go do that (can’t remember the GUI program’s name). If you don’t use a GUI, you can do this (in this example, I am assuming that the new hard drive showed up as “hdb”:
If you need help from here, I recommend you have a look at About.com’s guilde to Fdisk
Now, you will need to mount the new drive. Most people think you need to mount the drive in /mnt/ but that is not true. You can mount it in /var/www/ /home/<user_folder>/ or whatever place you like, so long as the directory you are mounting it to is currently empty. You can either mount it each time, or simply edit your /etc/fstab file
my fstab looks something like this:
# /etc/fstab: static file system information.
# <file system> <mount point> <type> <options> <dump> <pass>
proc /proc proc defaults 0 0
UUID=<random gibberish> ext3 defaults,errors=remount-ro 0 1
UUID=<random gibberish> none swap sw 0 0
/dev/scd0 /media/cdrom0 udf,iso9660 user,noauto,exec 0 0
I modified it slightly so you wouldn’t see my hard drive info (serial number). I replaced it with <random gibberish>
to add a drive, you would add something like this to the bottom of your fstab:
/dev/hdb1 /var/www ext3 defaults 0 0
You see how the hdb changed to hdb1? Well, that’s the new partition on the new drive. Each partition (be it 1, or 1000) gets a numeral at the end, starting with 1.
Rember, I’ve only been using hdb as an example. Yours may be different. It may be sda, sdb(those are SATA drives, usually). Just make sure you know which drive you are working with. If you get the wrong one, you could accidentally repartition your primary drive (I’m not sure if you actually can, but I’m covering my butt here).