In order to gain more Hard Disk space under Linux (as with any other Operating System), you would need to add a second Hard Disk (or replace your old one with something bigger, but since this would most likely require a re-install the first choice is preferable). In order to install a second Hard Disk under Linux theses are the steps involved:

1. Turn your system off and open the case, install the new drive and plug it into a free connector on your IDE cables.

2. Once your new hard disk is installed in your system, the drive should be autodetected boot time. In order to work out the drives device name under Linux you can simply work it from the list here:

Primary Controller First Drive:	/dev/hda
Primary Controller Second Drive:	/dev/hdb
Secondary Controller First Drive:	/dev/hdc
Secondary Controller Second Drive:	/dev/hdd

You will need to know this information to setup the drive under Linux.

3. Now that you know what your Hard Disk is referred to under Linux you will need to use fdisk to partition the drive e.g. fdisk /dev/hdb. The preferrable method is to select the old partitions and added a single Linux partition, making sure the partition type is 83 (Linux).

Type n to "add a new partition"
Type e to make it a "primary partition" (depending on how many partitions your creating)
Type 1 for a single partition
Enter the first cylinder e.g. 1
Enter the last cylinder e.g. 1245 (depending on the size of your drive)
Type w to write the partition table to disk and exit

4. When the partition has been created you need to create the file system by running mkfs. If you only created a single partition then it should be called something like this: /dev/hdb1, so you would only need to type: mkfs /dev/hdb1 in order to create the single file system. (This would work for multiple partitions but then you would need to run mkfs on each partition, e.g. mkfs /dev/hdb1 then mkfs /dev/hdb2 and so on until all your partitions have a file system).

This newly created file system should be created by default as ext2, if you want to create an ext3 file system (which is just ext2 + journal) then you will need to type tune2fs -j /dev/hdb1 (this will conver the ext2 to ext3) and the same for all partitions and file systems you created on your disk.

5. The next step is to make a mount point where you want the drive to be mounted, this can be done similar to this: mkdir /dir and then you can test mount the new filesystem: mount /dev/hdc1 /dir. The filesystem can then be unmounted using umount /dir.

6. Finally you will need to create an entry in /etc/fstab describing the new filesystem so it can be automatically mounted at boot time. This can be tested using mount all and observing that the new filesystem is indeed mounted. You will most likely need to add one or more lines similar to this:

/dev/hdX#     /dir/to/mount      extY     defaults     0 1

Where X is worked out from the list in part 2 above and # is the partition number. Enter Y as the file system you have created, i.e 2 for ext2 and likewise 3 for ext3.

Once you have completed this your machine is now ready with its increase Hard Disk capacity.