How to format a hard drive in Linux
With the release of Ubuntu Linux 8.10 many people are installing it for the first time.
Today’s question is How do I format my hard drive for linux if I already have something I don’t want on the hard drive?
At the command prompt, type “fdisk /dev/hdb” replacing the “hdb” with the letters for your drive. Upon opening, fdisk may give you a couple of warnings, all of which can be ignored. It then gives you a prompt that looks like this: Command (m for help):
Enter “p” to see the partition table of the drive. The first line of output from the “p” command will also tell you size of the drive. This is a good way to double check that you are working with the correct drive.
If there are any partitions already on the drive they will be listed as the last lines of the “p” command. On our example, this looks like “/dev/hdb1” followed by some information about the partition’s size and file system.
To delete any existing partitions, press “d” then enter. It will ask you which partition number you wish to delete. The number of the partition is the number that follows hdb, so on our example system we enter 1. If there are multiple partitions repeat the “d” command for each one. You can always view the partition table again with the “p” command.
Once you have deleted all existing partitions on the drive you are ready to make a new one. Type “n” and hit enter. Then press “p” to create a primary partition. It asks you for a partition number, enter “1.” Now you are asked which cylinder the partition should start at, the beginning of the drive is the default, so just hit Enter. Then you are asked for the last cylinder, the end of the drive is default so you can just press Enter again.
Now you are back at fdisk’s command prompt. Use the “p” command to check the partition table. You should now see your new partition at the bottom of the output. In the example it lists “/dev/hdb1.”
You now need to set the filesystem type for your new partition with the “t” command. You are asked for the Hex code of the filesystem you wish to use. We wll use the standard Linux ext2 filesystem which is “83.” If you are doing something special and know of a particular filesystem that you need to use, you can press “L” to see all the codes, which are one or two characters made up of the numbers 0-9 and the letters a-f.
Now just issue the “w” command to write your new partition table and exit fdisk.
Creating the New File System with mkfs
Now you need to create the filesystem on the drive. This is done with the “mkfs” command.
At the command prompt, enter “mkfs -t ext2 /dev/hdb1” while remembering to change the hdb1 to whatever the letters are for the partition you just created.
If you are using a different filesystem than ext2, you will have to specify that where “ext2″ is in the above command.
Finalizing the Format with fsck
All that is left is to run a check on the drive and enter it into your fstab so that the drive mounts each time you start your computer. This can be done with a single fsck command.
At the command prompt, type “fsck -f -y /dev/hdb1” again replacing hdb1 with the letters and number for your partition.
After fsck runs, your new drive is formatted. Restart your system before using it.
If you reformatted your system drive, you will now need to boot off an installation disk to install an Operating system.
