Home | Networking | Computer HWare/SWare | NOS: Unix/Linux | Favorites | Contact Me | RCC Home

Fdisk/Partioning

Most new computers come with one partition, your "C" drive.   So you would say that your hard drive has one primary partition.  A hard drive can have a total of four primary partitions.  If you have more than one hard drive in your computer you *could* have more than four primary partitions.

         extended partition     This is used after the primary partition.  So you could have three primary (or less) partitions and one extended partition.

         logical drives     These go inside the extended partition. You can have as many as you wish as long as you don't run out of drive letters.

A typical setup for a computer with one hard drive is to have one primary partition, one extended partition, and one to four logical drives (partitions) inside the extended partition. 

Primary partitions are assigned drive letters first, then logical drives (partitions) get drive letters next, and finally removable media devices (CD-ROM's, zip drives etc...) get drive letters last. 
I suggest making all removable media devices drive letters at the end of the alphabet.  An example, my CD-ROM is drive "X", my CD-ROM burner is drive "Y", and my zip drive is drive "Z".  This way no matter how you change your partitioning scheme your removable media drives can have consistent drive letter assignments.

Destructive VS. Non-destructive partitioning

Using FDISK (which comes with all versions of DOS and Win9x) is a destructive way to manage your partition(s). This means that if you create or destroy (you can't resize partitions with FDISK) you WILL DESTROY ALL DATA IN THE PARTITION(S)!!  Don't get into a hurry. 
I use Partition Magic by Powerquest .  This is a non-destructive way to create, resize, and add partitions. It's also very user friendly!

When you run FDISK it will prompt you whether to enable large disk support. If you answer yes, then any partition you create that is over 512 MB will use the FAT32 file system. If you answer no, then you will be unable to create disk partitions larger than 2GB. After creating a partition with FDISK, you must restart your computer and then format the drive before you can store data on it.

After you type FDISK you'll see the first screen giving you a question about enabling LBA generally say yes unless you want to use FAT 16. At the second screen you'll either start deleting partitions or creating partitions. Remember if you delete a partition you WILL LOSE ALL DATA IN THAT PARTITION!  Don't forget to make a primary partition active.  Otherwise when you reboot your computer it won't see any hard drives!

While you could have four primary partitions, FDISK will only allow you to create one.  There are other issues with FDISK as well, such as the fact that there are hidden switches that allow you to change the way FDISK works.   And it's almost impossible to create both FAT32 and FAT16 partitions on the same hard drive. The current version of FDISK will only make partitions greater than 512 meg FAT32

Here are the switches for FDISK.

         /PRI
Create a primary partition and set it active.
Example: FDISK /PRI:40 1
Creates a 40MB primary partition on disk #1
If the size is too large, the rest of the drive is used.

         /EXT
Same as /PRI, but for an extended partition. Does not set active.

         /LOG
Create a logical partition, MUST be used with /EXT on the same line
Example: FDISK /EXT:40 1 /LOG:40
Create a 40MB extended and puts a 40MB logical inside.

         PRIO
Like /PRI but always makes a FAT16 partition.
Normally /PRI will make anything larger than 512MB as FAT32?
(we think)

         /LOGO
Like /PRIO except for logical partitions.

         /Q
??? (we still don't know)

         /STATUS
I think this one is documented. Lists your partitions.

         /?
Help

         /MBR
Destroys and recreates the master boot record.

         /CMBR
Like MBR
except you can tell it which drive.

         /X
Never use "LBA mode" partition types.

         /ACTOK
Skip the "Checking drive integrity" thing.

         /FPRMT
Do not ask on startup if you want large disk support. Instead, ask when creating each partition if you want FAT16 or FAT32.  Also lets you use FAT32 on smaller drives.

Last but not least I'll give you a blow-by-blow example.  This assumes that you have one 4.3 gig hard drive, and that you want one primary partition (your "C" drive) and three logical partitions for the following... data, games, and the windows swap file. (NOTE: this is just one common setup)  REMEMBER, IF YOU MESS WITH AN EXISTING PARTITION ALL DATA WILL BE LOST!!

         Boot the computer with the boot disk.

         Type    FDISK     hit enter.

         Answer no if you want FAT16 or yes if you want FAT 32.

         ***Delete any existing partitions first before re-partitioning*** 
  (All logical partitions must be deleted before you can delete an extended partition)

         Create the primary partition which will be your "C" drive.

         Hit ESC back to the main menu.

         Follow the prompts to create the extended partition. (Be sure to use ALL the remaining free space!)

         Create your logical drives. 

At this point if you were careful you're done.  Look at this screen carefully and make sure it's how you want everything.  If it's not, start over.   Remember with FDISK you can't resize a partition later without destroying all data!

 


Home | Networking | Computer HWare/SWare | NOS: Unix/Linux | Favorites | Contact Me | RCC Home