There is a limit to how many ``primary'' and ``logical'' partitions a
drive can contain. Additionally, there are limits to where on the drive
the BIOS looks for boot information. More information can be found in the
Linux Partition mini-HOWTO. This section will include a brief overview to
help you plan most situations.

``Primary'' partitions are the original partitioning scheme for PC hard
disks. However, there can be only four of them. To get past this
limitation, ``extended'' or ``logical'' partitions were invented. By
setting one of your primary partitions as an extended partition, you can
subdivide all the space allocated to that partition into logical
partitions. The number of logical partitions you can create is much less
limited than the number of primary partitions you can create; however, you
can have only one extended partition per drive.

Linux limits the number of partitions per drive to 15 partitions for SCSI
drives (3 usable primary partitions, 12 logical partitions), and 63
partitions for IDE drives (3 usable primary partitions, 60 logical
partitions).

The last issue you need to know about a PC BIOS is that your boot
partition - that is, the partition containing your kernel image - needs to
be contained within the first 1,024 cylinders of the drive. Because the
root partition is usually your boot partition, you need to make sure your
root partition fits into the first 1,024 cylinders.

If you have a large disk, you may have to use cylinder translation
techniques, which you can set in your BIOS, such as LBA translation mode.
(More information about large disks can be found in the Large Disk
mini-HOWTO.) If you are using a cylinder translation scheme, your boot