Designing a hard disk layout.

Designing a hard disk layout is a good way to tailor a system to your particular needs. Linux allows for the creation of multiple partitions, and each partition can be used as a different mount point for various directories of the file system.

Most default Linux installs use a generic partition scheme which usually creates two partitions, one for the Linux filesystem and one used as a swap space, similar to virtual memory under Windows. This is generally sufficient for most users, but better control and system performance can be gained with a well designed layout.

Here is a brief overview of the movable Linux directories and what they contain:

/boot: contains the systems critical boot files.
/home: contains the data files and home directories for each user on the system.
/mnt: used as a mount point for removable media
/media: similar to /mnt
/opt: Contains Linux files and programs associated with third party software.
/tmp: Contains temporary files created by ordinary users.
/usr: Contains most Linux program and data files.
/usr/local: contains programs and files unique to particular installation.
/var: holds files associated with the day to day functioning of the computer.
The other directories(/etc,/bin,/sbin,/lib, and /dev) should never be placed on separate partitions as they are critical to the functioning of the base system and should reside under the main Linux partition.

The best time to set up partitions is when doing a fresh installation or when re-formating and re-installing. While it may be possible to re-work an installed system from a live cd or rescue disk, I highly doubt this would be a good idea.

With all that out of the way, let's look at some possible layouts.

For a basic home system, making a /boot partition, a /(root) partition, a /home partition, and a swap partition. The /boot partition can be ext2 while the others should be ext3, ext4, or some other type of journaling filesystem. Having a separate /home partition allows you to re-install the rest of the operating system without having to reformat and lose the information on the
/home partition. When re-installing, simply format /boot and / and leave /home alone.

As for sizes, /boot should be 50-100 MB, the swap partition is generally 1.5 to 2 times system RAM, and the / and /home partitions should each be half of the remaining space. This arrangement should give a Desktop system good performance and reliability, with plenty of space for both user files and software installations/updates.

For servers, a similar arrangement can be used, but /var should also be a separate partition as it is often used by various server programs. Also, on a server /home likely does not need to be as large as the / or /var partitions since servers generally don't make large use of /home.

Keep in mind that these are guidelines, and a starting point for your options. Also, if you plan to create more than four partitions, you will have to use logical partitions for some or all of them as you are only allowed four primary partitions on a hard disk.