Partitioning a Hard Disk

There are several programs to create and remove partitions. Several of the programs are known as fdisk, in Linux and its variations. Details on using the Linux fdisk are provided on its man page. The cfdisk command is same to fdisk, but has a full-fledged (full screen) user interface.

Whenever we using IDE disks, the boot partition (the partition along with the bootable kernel image files) must be finished inside the first 1024 cylinders. That is due to the fact in which the disk is utilized by the BIOS during boot (before the system goes into protected mode) and BIOS will not handle more than 1024 cylinders. This is sometimes probable to use a boot partition which is only partly inside the first 1024 cylinders. This works as long as all the files which are read with the BIOS are inside the first 1024 cylinders. Because this is hard to arrange, the user may not know whenever a kernel update or disk defragmentation would result in an unbootable system. Thus, the boot partition should be completely inside the first 1024 cylinders.

Newer versions of the IDE and BIOS disks can handle disks with more than 1024 cylinders.

Every partition should have an even number of sectors. Because the Linux filesystems use a 1-kilobyte block size, which is, two sectors, an odd number of sectors will result in the last sector being unused.

Modification a partition's size commonly needed first backing up the files to be saved from which partition (preferably the whole disk, just in case), creating a new partition, deleting the partition, then restoring everything to the new partition. The sizes (and backup and restore) of the adjoining partitions required to be adjusted as well if the partition grows.

Because changing the size of partitions is tedious, this is preferable to get the partitions right the first time, or have an effectual and easy-to-use backup system. If installation is done from a media which does not need much human intervention (for example, from CD-ROM, as opposed to floppies), it is frequent simple to play with different configurations. Because there is no data to be backed up it is not tedious to change the size of the partition various times.

There is a program for MS-DOS, known as fips, that resizes an MS-DOS partition without need the backup and restore, but for other filesystems it is still must.

Note: In Sun Solaris, the format command can be used to make or change partition in a disk. After selecting the disk, the format menu is displayed; partition should be selected to display the partition menu. The required command is provided in the menu to modify and change the partition.