|
Understanding Hard Disks and Partitions |
A magnetic disk on which you can store computer data. The term hard is used to distinguish it from a soft, or floppy, disk. Hard disks hold more data and are faster than floppy disks. A hard disk, for example, can store anywhere from 10 megabytes to several gigabytes, whereas most floppies have a maximum storage capacity of 1.4 megabytes.
A single hard disk usually consists of several platters. Each platter requires two read/write heads, one for each side. All the read/write heads are attached to a single access arm so that they cannot move independently. Each platter has the same number of tracks, and a track location that cuts across all platters is called a cylinder. For example, a typical 84 megabyte hard disk for a PC might have two platters (four sides) and 1,053 cylinders.
In general, hard disks are less portable than floppies, although it is possible to buy removable hard disks.
Fdisk Command Tutor
http://www.computerhope.com/fdiskhlp.htm
Fdisk Screenhots
http://www.computerhope.com/sfdisk1.htm
Hard Disk Logical
Structures and File Systems
http://www.pcguide.com/ref/hdd/file/index.htm
Describes "standard" file systems used on PCs, with particular focus
on the FAT file system and its variants. This page is from "The PC Guide."
PC Guide's hard disk drive
reference
http://www.pcguide.com/ref/hdd/
Offers a large amount of information covering construction and operation,
geometry and formatting, performance factors, BIOS and size issues, interfaces,
configuration and file systems.
Hard Disk BIOS and Capacity
Factors
http://www.pcguide.com/ref/hdd/bios/index.htm
Describes issues related to how the BIOS and operating system interact
with the hard disk, and BIOS-related issues and problems. Includes a full
look at the many capacity limitations inherent in using IDE/ATA interface
drives, and other BIOS restrictions on hard disk capacity. This page is
from "The PC Guide."
Hard Disk BIOS Translation
Modes
http://www.pcguide.com/ref/hdd/bios/modes.htm
Detailed description of the various types of BIOS translation that
are used in modern PCs. Includes sections on normal/standard CHS mode,
Extended CHS/large mode, Logical Block Addressing (LBA), a comparison of
translation modes, and caveats on changing translation modes and transferring
hard disks between PCs. This page is from "The PC Guide."
Hard Disk Help
http://www.zdnet.com/pcmag/pctech/content/solutions/packs/harddisk.html
Various articles, from PC Magazine, on how to keep your hard disk in
tip-top shape.
Hook-up a New Hard Drive
http://www.webshopper.com/jhtml/features/howTo.jhtml?aid=164027&cid=51567
Shake the cramps out of your storage system with our EIDE hard disk
upgrade guide.
Hard disk information page
http://www4.tomshardware.com/guides/storage.html
This site hosts a collection of information on hard disks, including
an EIDE FAQ, the bus master DMA features and drivers and troubleshooting,
driver information, and manufacturer pages.
Hard Disk Troubles
http://www.zdnet.com/pcmag/pctech/content/17/22/tu1722.001.html
PC Magazine article (December 1998) that examines hard disk construction
and operation, errors and repairs, and installation.
To divide memory or mass storage into isolated sections. In DOS systems, you can partition a disk, and each partition will behave like a separate disk drive. Partitioning is particularly useful if you run more than one operating system. For example, you might reserve one partition for Windows and another for UNIX.
In addition, partitioning on DOS and Windows machines can improve disk efficiency. This is because the FAT system used by these operating systems automatically assigns cluster size based on the disk size: the larger the disk, the larger the cluster. Unfortunately, large clusters can result in a wasted disk space, called slack space. There is an entire sector of the software industry devoted to building utilities that let you partition your hard disk.
On Apple Macintosh computers, there are two types of partitioning: hard and soft. Hard partitioning is the same as DOS partitioning -- the disk is physically divided into different sections. Soft partitioning, on the other hand, does not physically affect the disk at all, but it fools the Finder into believing that the disk is partitioned. The advantage of this is that you can partition the disk without affecting the data on it. With hard partitioning, it is usually necessary to reformat the entire disk.
A section of main memory or mass storage that has been reserved for
a particular application.
Hard Disk Logical
Structures and File Systems
http://www.pcguide.com/ref/hdd/file/index.htm
Describes "standard" file systems used on PCs, with particular focus
on the FAT file system and its variants. This page is from "The PC Guide."
Partitioning Your Hard Disks
http://www.zdnet.com/pcmag/pctech/content/16/11/tu1611.001.html
PC Magazine tutorial article on how to squeeze extra storage out of
large capacity drives with more efficient partitions. Provides very good
background information as well as an explanation of FAT32.
Getting the Boot
http://pclt.cis.yale.edu/pclt/BOOT/DEFAULT.HTM
Describes how to plan, partition, install, and remove DOS, OS/2, NT,
and other operating systems on the same disk at the same time. Includes
information on how to diagnose boot time failures. Topics include: FDISK,
MBR, BootManager, Dual Boot, boot sectors, primary partitions, and logical
volumes.
Hard drive terms and tricks
http://www.computercraft.com/docs/evsterms.html
Describes several terms associated with hard drives (cache, BIOS, chips,
partition, etc.) and their associated functions.
This can cause a lot of confusion and problems if not understood, so take the time to grasp it before using multiple primary partitions, either on multiple disks or on a single disk.
First of all, there are four allowed primary partitions per disk, one of which may be an extended type. This extended type of partition must contain at least one logical partition, but can contain up to 20.
Windows 95 or 98 must boot from a primary partition, not extended-logical. It also must boot from the first recognized disk in the system, the primary master.
Remember this: The partition that Windows 9x boots from is always given the letter C:
The result is that letters change as you switch systems and you need to be aware of it, especially when installing new systems.
The order of disks can be altered in several ways in order to boot from a given disk:
1) Switching jumpers (too much trouble)
2) Enabling Disk Swap in BIOS (not available in many motherboards and also too much trouble)
3) Using a boot manger like Bootit Direct
When you switch boot drives/partitions and boot a different system, the letters assigned your primary and logical partitions change according to the following table:
C:
The primary partition that is booted
D:
The active partition on the secondary disk, or if none is active, the
partition closest to the outside
Next
The active or first primary partitions on each other disk in sequence:
Primary Master, Primary Slave, Secondary Master, Secondary Slave. (as seen
by the system)
Next
The logical partitions on all disks in the same sequence
Next
The second third and fourth primary partitions in sequence on each
disk.
Next
Virtual drives such as drivespace hosts.
============================================
Side note. What would you need to know to make a bootdisk for my Primary
Slave on this system bootable???
Well there's a few ways to do this, but I try and narrow that to two of them, one quick and dirty and the other more techie.
Quick and dirty (also the easiest when working with an existing system).
1. Make sure that your primary slave has all the files that are on your primary.
2. Create a boot disk, but transfer all the winboot files to it that windows uses to boot.
3. Now, the work. You'll have to change some registry entries to allow
you to boot from "A" and work with "D" (or whatever letter designation
it is). A good example would be a system that boots to a SCSI drive. The
boot files are either on a floppy or on an IDE hard drive, but everything
else, including windows is on the SCSI drive. For instance, when "win.com"
is called, it should be called "at" D:\Windows. Since your apparently working
with files that you have transferred from "C", and that being the original
"installed to" drive, you'll have to be careful in changing your registry
entries.
Boot the system into the motherboards' Bios\Cmos setup. This may require you to tap the DEL key, or F1 or F8 or whatever during the boot process. Check the settings and look for a section to use setup defaults and use those as a start. Next, look for a section that refers to plug and play operating system and enable it. Now save the settings. This may take a little more tweaking, but this is a start.
Now boot into windows 98 SAFEMODE. Go into Control Panel, System Icon and then the Device Manager tab. Scroll down to the device areas and click the + to exapnd it. Highlight each item and click remove.
Now reboot the system. Windows will find the devices and may ask for
your Win98 CD for the drivers. Load the CD and let it load the drivers
and you should be good to go.
From:
http://www.quantum.com/app_notes/app_note_ata_drvletters.htm
All ATA/IDE Disk Products
Overview
When you add a drive to a system the lettering scheme can change and
what had been your "D:" drive may be reassigned another letter. This is
due to the hierarchy that Windows and DOS use to assign drive letters.
That hierarchy is as follows:
-- Primary Master primary partition
-- Primary Slave primary partition
-- Secondary Master primary partition
-- Secondary Slave primary partition
-- Primary Master extended partition with logical drives
-- Primary Slave extended partition with logical drives
-- Secondary Master extended partition with logical drives
-- Secondary Slave extended partition with logical drives
-- Removable media (CD-ROM) or other software driven devices with drive
letters
Resolution
When you add the new drive, creating a primary partition on it with FDISK will force all extended partitions and logical drives to a new letter assignment.
To avoid this, set up the new drive with only an extended partition, with logical drives. This will keep the drive letters for the fixed disks in the same order, assuming you are not inserting the new drive as a Primary Slave, with an existing Secondary Master already in the system.
You can also move the data from the old D: drive to the new D: drive
using the XCOPY command. The command would look like this XCOPY E: D: /h/e/c/r/y.
This would make an exact duplicate of the drive that had been D: Check
your operating system manual for the supported switches for your version
of XCOPY.