TOPIC A
Install and Configure Storage Devices
In this lesson, you will install and configure system components. Storage devices such as hard disks are one of the most common system components you will install. In this topic, you will install and configure storage devices.
Users rely on local storage devices to keep their applications and data current and available. As an A+ technician, your responsibilities are likely to include installing and configuring dif- ferent types of storage devices to provide your users with the data-storage capabilities that they need to perform their jobs.
Hard Disk Drive Types
There are many types of hard disks as well as the hard disk controllers that enable the disk to connect to the system board.
For IDE drives, ATA was the formal name chosen by the American National Standards Insti-
tute (ANSI) group X3T10. It specifies the interface specifications for the power and data
signals between the system board, the drive controller, and the drive.
Install and Configure Storage Devices
In this lesson, you will install and configure system components. Storage devices such as hard disks are one of the most common system components you will install. In this topic, you will install and configure storage devices.
Users rely on local storage devices to keep their applications and data current and available. As an A+ technician, your responsibilities are likely to include installing and configuring dif- ferent types of storage devices to provide your users with the data-storage capabilities that they need to perform their jobs.
Hard Disk Drive Types
There are many types of hard disks as well as the hard disk controllers that enable the disk to connect to the system board.
Extending IDE Drive Capabilities
The original IDE specification limits hard drive size to 504 MB. Three ways were developed to overcome this limitation.
The original IDE specification limits hard drive size to 504 MB. Three ways were developed to overcome this limitation.
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● You can extend the drive size limit to 8.4 GB through the use of Logical Block Address-
ing (LBA) or Extended CHS (ECHS). With LBA or ECHS, hard drives can be up to 8.4
GB in size. LBA and ECHS are methods of sector translation (translating a hard drive’s
logical geometry into physical geometry) that essentially give the BIOS incorrect informa-
tion about the geometry of the drive so that larger hard-drive capacities can be supported,
while staying within BIOS limitations. The cylinder value after translation never exceeds
1,024. LBA was developed by Western Digital. ECHS was developed by Seagate. They
differ only in the sector translation results they produce. If you want to move a hard drive
from one computer to another, then the other computer must support the same sector
translation method as the computer from which you are removing the hard drive. Other-
wise, you will lose the data on the disk if you move the drive. This is a problem mostly if
one computer is significantly older than another. But you do want to check and always
back up your data before moving a drive. Today’s hard disks and BIOSs all support LBA
and ECHS to accommodate the need for large disk capacity.
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● To address the need for even larger hard drive capacities, Phoenix Technologies developed
Interrupt 13h (INT13h) extensions. Developed in 1994, INT13h extensions are a newer set
of BIOS commands that enable support for hard drives larger than 8.4 GB. This support
is made possible by using 64 bits for addressing, instead of 24 bits, and by using 1,024 cylinders. This expands hard drive support for drives up to 137 GB. INT 13h extensions are supported by modern hard drives and Windows 95 and newer operating systems, but must also be supported by the system BIOS or the hard-disk controller.
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● If you need to support hard disks greater than 137 GB, you can use large LBA translation
mode. It uses 48 bits for addressing instead of 24 bits.
PIO Modes
The ATA and ATA-2 standards use the Programmed Input/Output Mode (PIO Mode) to indicate the speed of data transfer between two devices that use the computer’s processor as a part of the datapath. The PIO Mode is set in the BIOS. It is originally set when you install an IDE or EIDE drive. The following table lists the transfer rate for several ATA and ATA-2 standards.
Standard/PIO Mode
ATA/0 ATA/1 ATA/2 ATA-2/3 ATA-2/4
IDE Drives and ATA Specifications
ATA/0 ATA/1 ATA/2 ATA-2/3 ATA-2/4
IDE Drives and ATA Specifications
Data Transfer Rate
3.3 MBps 5.2 MBps 8.3 MBps 11.1 MBps 16.6 MBps
3.3 MBps 5.2 MBps 8.3 MBps 11.1 MBps 16.6 MBps
The manufacturer can use any physical interface, but must have an embedded controller that
uses the ATA interface controller to connect the drive directly to the ISA bus.
The original IDE specification did not support CD-ROMs or hard drives larger than 528 or 504 MB. However, revisions of the specifications over the years have extended the capabilities to provide support for faster and larger hard drives. The following table describes ATA specifications.
The original IDE specification did not support CD-ROMs or hard drives larger than 528 or 504 MB. However, revisions of the specifications over the years have extended the capabilities to provide support for faster and larger hard drives. The following table describes ATA specifications.
Standard
ATA
ATA-2
ATA-3
ATAPI ATA-4 ATA-5
ATA-6
PIO
DMA
Ultra DMA 100
ATA
ATA-2
ATA-3
ATAPI ATA-4 ATA-5
ATA-6
PIO
DMA
Ultra DMA 100
Description
The original ATA specification supported one channel, with two drives configured in a master/slave arrangement. PIO modes 0, 1, and 2 were supported, as well as single-word DMA modes 0, 1, and 2 and multi-word DMA mode 0. No support for non-hard disk devices was included, nor were block mode transfers, logical block addressing, and other advanced features.
Also known as the Advanced Technology Interface with Extensions. Western Digital’s implementation was called Enhanced IDE (EIDE). Seagate’s implementation was called Fast ATA or Fast ATA-2. Sup- ports PIO modes 3 and 4 and two multi-word modes, 1 and 2, all of which are faster than the modes supported by the original ATA specification. Support for 32-bit transactions. Some drives supported DMA. Could implement power-saving mode features if desired. Specification also covered removable drives.
Minor enhancement to ATA-2. Improved reliability for high-speed data transfer modes. Self Monitoring Analysis And Reporting Tech- nology (SMART) was introduced. This is logic in the drives that warns of impending drive problems. Password protection available as a security feature of the drives.
AT Attachment Packet Interface is an EIDE interface component that includes commands used to control tape and CD-ROM drives.
Also known as Ultra-DMA, UDMA, Ultra-ATA, and Ultra DMA/33. Doubled data transfer rates. Supported ATAPI specification.
The ATA-5 specification introduced Ultra DMA modes 3 and 4, as well as mandatory use of the 80-pin, high-performance IDE cable. Additional changes to the command set were also part of this specification. Supports drives up to 137 GB.
Supports Ultra DMA/100 for data transfers at up to 100 MB/second. Supports drives as large as 144 PB (petabytes), 144 million MB, or 144 quadrillion bytes.
Programmed Input/Output is a data transfer method that includes the CPU in the data path. It has been replaced by DMA and Ultra DMA.
Direct Memory Access is a data transfer method that moves data directly from the drive to main memory. Ultra DMA Transfers data in burst mode at a rate of 33.3 MB per second. The speed is two times faster than DMA.
Also known as ATA-100, this standard supports data transfers in burst mode at a rate of 100 MB per second.
The original ATA specification supported one channel, with two drives configured in a master/slave arrangement. PIO modes 0, 1, and 2 were supported, as well as single-word DMA modes 0, 1, and 2 and multi-word DMA mode 0. No support for non-hard disk devices was included, nor were block mode transfers, logical block addressing, and other advanced features.
Also known as the Advanced Technology Interface with Extensions. Western Digital’s implementation was called Enhanced IDE (EIDE). Seagate’s implementation was called Fast ATA or Fast ATA-2. Sup- ports PIO modes 3 and 4 and two multi-word modes, 1 and 2, all of which are faster than the modes supported by the original ATA specification. Support for 32-bit transactions. Some drives supported DMA. Could implement power-saving mode features if desired. Specification also covered removable drives.
Minor enhancement to ATA-2. Improved reliability for high-speed data transfer modes. Self Monitoring Analysis And Reporting Tech- nology (SMART) was introduced. This is logic in the drives that warns of impending drive problems. Password protection available as a security feature of the drives.
AT Attachment Packet Interface is an EIDE interface component that includes commands used to control tape and CD-ROM drives.
Also known as Ultra-DMA, UDMA, Ultra-ATA, and Ultra DMA/33. Doubled data transfer rates. Supported ATAPI specification.
The ATA-5 specification introduced Ultra DMA modes 3 and 4, as well as mandatory use of the 80-pin, high-performance IDE cable. Additional changes to the command set were also part of this specification. Supports drives up to 137 GB.
Supports Ultra DMA/100 for data transfers at up to 100 MB/second. Supports drives as large as 144 PB (petabytes), 144 million MB, or 144 quadrillion bytes.
Programmed Input/Output is a data transfer method that includes the CPU in the data path. It has been replaced by DMA and Ultra DMA.
Direct Memory Access is a data transfer method that moves data directly from the drive to main memory. Ultra DMA Transfers data in burst mode at a rate of 33.3 MB per second. The speed is two times faster than DMA.
Also known as ATA-100, this standard supports data transfers in burst mode at a rate of 100 MB per second.
Standard
Serial ATA
Serial ATA II
SCSI Standards
Serial ATA
Serial ATA II
SCSI Standards
Description
Uses serial instead of parallel signaling technology for internal ATA and ATAPI devices. Serial ATA employs serial connectors and serial cables, which are smaller, thinner, and more flexible than traditional parallel ATA cables. Data transfer rates are 150 MB per second or greater.
Also known as SATA 3.0, SATA 3.0 Gb/s, and SATA/100. Provides data transfer rates of 300 MB/sec.
Uses serial instead of parallel signaling technology for internal ATA and ATAPI devices. Serial ATA employs serial connectors and serial cables, which are smaller, thinner, and more flexible than traditional parallel ATA cables. Data transfer rates are 150 MB per second or greater.
Also known as SATA 3.0, SATA 3.0 Gb/s, and SATA/100. Provides data transfer rates of 300 MB/sec.
SCSI standards have been revised repeatedly over the years. The following table describes cur-
rent SCSI standards.
SCSI Stan-
dard
SCSI-1
SCSI-2
SCSI-3
SCSI-1
SCSI-2
SCSI-3
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Ultra-2 SCSI
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Ultra-3 SCSI
Description
Features an 8-bit parallel bus (with parity), running asynchronously at 3.5 MB/s or 5 MB/s in synchronous mode, and a maximum bus cable length of 6 meters, compared to the 0.45-meter limit of the Parallel ATA interface. A variation on the original standard included a high-voltage differential (HVD) implementation with a maximum cable length of 25 meters.
Introduced the Fast SCSI and Wide SCSI variants. Fast SCSI doubled the maximum transfer rate to 10 MB/s, and Wide SCSI doubled the bus width to 16 bits to reach 20 MB/s. Maximum cable length was reduced to 3 meters.
The first parallel SCSI devices that exceeded the SCSI-2 capabilities were simply designated SCSI-3. These devices were also known as Ultra SCSI and Fast-20 SCSI. The bus speed doubled again to 20 MB/s for narrow (8 bit) systems and 40 MB/s for wide (16-bit). The maximum cable length stayed at 3 meters.
This standard featured a low-voltage differential (LVD) bus. For this reason Ultra-2 SCSI is sometimes referred to as LVD SCSI. LVD’s greater immu- nity to noise allowed a maximum bus cable length of 12 meters. At the same time, the data transfer rate was increased to 80 MB/s.
Also known as Ultra-160 SCSI, this version was basically an improvement on the Ultra-2 SCSI standard, in that the transfer rate was doubled once more to 160 MB/s. Ultra-160 SCSI offered new features like cyclic redun- dancy check (CRC), an error correcting process, and domain validation.
This standard doubled the data transfer rate to 320 MB/s.
Also known as Fast-320 SCSI, Ultra-640 doubles the interface speed yet again, this time to 640 MB/s. Ultra-640 pushes the limits of LVD signaling; the speed limits cable lengths drastically, making it impractical for more than one or two devices.
Features an 8-bit parallel bus (with parity), running asynchronously at 3.5 MB/s or 5 MB/s in synchronous mode, and a maximum bus cable length of 6 meters, compared to the 0.45-meter limit of the Parallel ATA interface. A variation on the original standard included a high-voltage differential (HVD) implementation with a maximum cable length of 25 meters.
Introduced the Fast SCSI and Wide SCSI variants. Fast SCSI doubled the maximum transfer rate to 10 MB/s, and Wide SCSI doubled the bus width to 16 bits to reach 20 MB/s. Maximum cable length was reduced to 3 meters.
The first parallel SCSI devices that exceeded the SCSI-2 capabilities were simply designated SCSI-3. These devices were also known as Ultra SCSI and Fast-20 SCSI. The bus speed doubled again to 20 MB/s for narrow (8 bit) systems and 40 MB/s for wide (16-bit). The maximum cable length stayed at 3 meters.
This standard featured a low-voltage differential (LVD) bus. For this reason Ultra-2 SCSI is sometimes referred to as LVD SCSI. LVD’s greater immu- nity to noise allowed a maximum bus cable length of 12 meters. At the same time, the data transfer rate was increased to 80 MB/s.
Also known as Ultra-160 SCSI, this version was basically an improvement on the Ultra-2 SCSI standard, in that the transfer rate was doubled once more to 160 MB/s. Ultra-160 SCSI offered new features like cyclic redun- dancy check (CRC), an error correcting process, and domain validation.
This standard doubled the data transfer rate to 320 MB/s.
Also known as Fast-320 SCSI, Ultra-640 doubles the interface speed yet again, this time to 640 MB/s. Ultra-640 pushes the limits of LVD signaling; the speed limits cable lengths drastically, making it impractical for more than one or two devices.
Storage Area Networks
In addition to the technologies you see for increasing the drive space on workstations, many companies now implement technologies such as storage area networks (SANs). A SAN is a Fibre Channel network designed to attach storage devices such as drive arrays and tape librar- ies to servers. Most SANs use the SCSI protocol to communicate with these devices, along with the high-speed Fibre Channel interface. The advantage to a SAN is that you can easily move its storage from one server to another. In addition, you can configure a server to boot from a SAN, which means that if the server fails, you can quickly configure another server to use the SAN and thus replace the failed server.
Network-Attached Storage
In contrast to Storage Area Networks, network-attached storage (NAS) refers to storage devices that are dedicated storage servers. These devices enable users to access their data even when other servers are down. The drawback to NAS devices is that their performance depends on the speed of and traffic on your existing network.
Floppy Disk Drives
Internal floppy drives connect to the system board through a floppy disk controller. The drive can access data on the disk directly and spins at about 360 RPM. The form factor of floppy drives is usually 3.5 inches. Depending on the number of sectors per track on the disk, 3.5- inch floppy disks can hold 720 KB or 1.44 MB of data; the floppy drive can accommodate either disk capacity.
Tape drives come in several formats.
CD and DVD drives have varying characteristics and specifications.
In addition to the technologies you see for increasing the drive space on workstations, many companies now implement technologies such as storage area networks (SANs). A SAN is a Fibre Channel network designed to attach storage devices such as drive arrays and tape librar- ies to servers. Most SANs use the SCSI protocol to communicate with these devices, along with the high-speed Fibre Channel interface. The advantage to a SAN is that you can easily move its storage from one server to another. In addition, you can configure a server to boot from a SAN, which means that if the server fails, you can quickly configure another server to use the SAN and thus replace the failed server.
Network-Attached Storage
In contrast to Storage Area Networks, network-attached storage (NAS) refers to storage devices that are dedicated storage servers. These devices enable users to access their data even when other servers are down. The drawback to NAS devices is that their performance depends on the speed of and traffic on your existing network.
Floppy Disk Drives
Internal floppy drives connect to the system board through a floppy disk controller. The drive can access data on the disk directly and spins at about 360 RPM. The form factor of floppy drives is usually 3.5 inches. Depending on the number of sectors per track on the disk, 3.5- inch floppy disks can hold 720 KB or 1.44 MB of data; the floppy drive can accommodate either disk capacity.
How Floppy Disk Drives Work
When you insert a floppy disk into a floppy disk drive:
Floppy disks can be protected so that you cannot write over data on the disk. On the back side of the floppy disk, you will see a slider in the upper-left corner. If the slider is pushed down, it blocks the write-protect hole and enables you to write to the floppy disk. If the slider is pushed up and the write-protect hold is visible, you will not be able to write to the disk.
Tape Drive Types
When you insert a floppy disk into a floppy disk drive:
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The metal door on the disk slides open, revealing the Mylar disk surface.
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The controller motor spins the floppy disk at about 360 RPMs.
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A worm gear operated by a stepper motor (a motor that moves in fixed increments) moves
the read/write heads (one on each side of the disk) to the desired track.
Floppy disks can be protected so that you cannot write over data on the disk. On the back side of the floppy disk, you will see a slider in the upper-left corner. If the slider is pushed down, it blocks the write-protect hole and enables you to write to the floppy disk. If the slider is pushed up and the write-protect hold is visible, you will not be able to write to the disk.
Tape Drive Types
How Tape Drives Work
While hard drives, floppy drives, and removable cartridge drives are direct-access devices, tape drives are sequential access devices. Rather than being able to go to a specific file directly, with a tape, you have to read past every file on the tape until you get to the one you want. For this reason, tape drives are typically used to store backup copies of information, as opposed to for live data access. When you insert a tape cartridge in a tape drive and perform a backup of files from your hard drive:
Optical drives include CD and DVD drives. They can be connected via IDE, SCSI, USB, FireWire, or parallel interfaces. Some optical drives provide only read capabilities, while others enable users to write, or burn, data to optical disks. Optical drives can be internal or external. Internal optical drives have a 5.25-inch form factor. The following table describes optical drive specifications.
While hard drives, floppy drives, and removable cartridge drives are direct-access devices, tape drives are sequential access devices. Rather than being able to go to a specific file directly, with a tape, you have to read past every file on the tape until you get to the one you want. For this reason, tape drives are typically used to store backup copies of information, as opposed to for live data access. When you insert a tape cartridge in a tape drive and perform a backup of files from your hard drive:
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The computer reads the file system table on the hard drive, locates the files that you want
to back up, and begins reading file data into RAM.
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Data is then dumped from RAM to the tape drive controller buffer as memory fills.
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The controller sends commands to the drive to start spooling the tape.
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The capstan in the center of the supply reel turns the rollers in the cartridge. The belt
around the tape and the rollers provide resistance and keep the tape taught and tight to the
drive heads.
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Data is sent from the controller to the read/write heads.
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The tape is composed of parallel tracks. Data is written from the center out towards the
edge on each pass. Holes in the end of the tape signal when the direction of the tape
needs to be reversed. When it gets to the end, it reverses and moves out one track.
Optical drives include CD and DVD drives. They can be connected via IDE, SCSI, USB, FireWire, or parallel interfaces. Some optical drives provide only read capabilities, while others enable users to write, or burn, data to optical disks. Optical drives can be internal or external. Internal optical drives have a 5.25-inch form factor. The following table describes optical drive specifications.
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