Partition with fdisk

fdisk is started by typing (as root) fdisk device at the command prompt. device might be something like /dev/hda or /dev/sda.

To check the list of devices available type fdisk -l

The basic fdisk commands you need are:

p – Print the partition table.

n – Create a new partition.

d – Delete a partition.

q – Quit without saving changes.

a – Make a partition bootable.

w – Write the new partition table and exit.

Changes you make to the partition table do not take effect until you issue the write (w) command. Here is a sample partition table:

Disk /dev/sdb: 64 heads, 63 sectors, 621 cylinders Units = cylinders of 4032 * 512 bytes    Device Boot    Start       End    Blocks   Id  System /dev/sdb1   *         1       184    370912+  83  Linux /dev/sdb2           185       368    370944   83  Linux /dev/sdb3           369       552    370944   83  Linux /dev/sdb4           553       621    139104   82  Linux swap

Now here is how to partition a USB Drive for example:

1.      Type: fdisk /dev/sda or fdisk /dev/sdb (whatever may be your drive; to be sure which one is your drive just enter the USB Stick and check in the /dev, you will see a new device sda or sdb or sdc etc. is shown which was not there before inserting the stick.)

2.      Type: p to print the partition table of this device.

Command (m for help): p

Disk /dev/sdb: 64 heads, 63 sectors, 621 cylinders

Units = cylinders of 4032 * 512 bytes

3.      Now to create new partition type: n

        Command (m for help): n

        Command action

           e   extended

           p   primary partition (1-4)

Type: p for primary partition, and then do the following:

Partition number (1-4): 1

First cylinder (1-621, default 1) :<ENTER>

Using default value 1

Last cylinder or +size or +sizeM or +sizeK (1-621, default 621):+384M

+384 – This is the size of the partition in MB; give whatever size you want.

4.      Next to set up the partition for swap, just create another partition the same way:

Command (m for help): n

Command action

   e   extended

   p   primary partition (1-4)

p

Partition number (1-4): 2

First cylinder (197-621, default 197):

Using default value 197

Last cylinder or +size or +sizeM or +sizeK (197-621, default 621): +128M

2 more partitions can be created the same way.

5.      Make the first partition bootable:

Command (m for help): a

Partition number (1-4): 1

6.      Make second partition of type swap:

Command (m for help): t

Partition number (1-4): 2

Hex code (type L to list codes): 82

Changed system type of partition 2 to 82 (Linux swap)      

Command (m for help): p

7.      Finally issue a write command w to write the partition on to the disk. Without this command the changes will not be retained.