Transcript Removeable Drives

Floppy Disk Drive
Rear view of floppy disk drive
Front view 3.5-inch floppy disk drive
Data cable
3.5-inch floppy disk
Power cable
How Floppy Disk Drives Work
Read/write heads
Connectors for a Typical Floppy Disk
Drive
Disk drive
Power connection
Data connection
34-pin ribbon cable
Optical Drives
An external DVD drive
A CD-R disc
An internal CD-ROM drive
Connectors for a Typical CD-ROM
Drive
CD-ROM drive
Audio out
Jumpers
40-pin connectors
Molex power connector
Common Problems with Optical Drives
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Misaligned case
Tray out of balance
Drive mechanism won’t pull disc or tray in
CD drive won’t release the CD
Disconnected wires
Driver problems
Overheating
Software
Default audio device not set to system’s audio device
Cartridge Drives
Rear view of SCSI external
Zip drive
External Jaz cartridge drive
with cartridge inserted
Zip cartridge
How Removable Cartridge Drives
Work
Hub
Read/write heads
Syquest Drives
Name
Description
SparQ
A 1 GB cartridge for PCs with a parallel port or EIDE
interface. The speeds are equivalent to most hard
disks.
SyJet
A 1.5 GB cartridge for PCs and Macs. Interface
choices include parallel port, and internal and
external EIDE and SCSI. Macs can only use the
SCSI version. Seek time is 12 ms and average
transfer rate is 6.9 MB per second.
Zip Drives
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Slightly larger and twice as thick as a regular 3.5inch disk.
The Zip drive can only read Zip disks.
Along with the original 100 MB Zip disk, currently
there are 250 MB and 750 MB versions.
Iomega’s Zip drives can be used in both PCs and
Macs.
Connection options now include external USB,
FireWire, parallel, and SCSI; as well as internal
ATAPI.
Jaz Drives
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Comes in 1 GB and 2GB versions.
The 2 GB drive can also read 1 GB cartridges.
Considered a legacy drive as it is no longer
manufactured.
Currently the Iomega corporation only supports the
2 GB internal SCSI and external Ultra SCSI models.
Can be used in both PCs and Macs.
SuperDisk Drives
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Uses super-high-density floppy disks formatted in a
servo pattern with 2,490 tracks.
120 MB capacity per disk.
Can also read regular 1.44 MB floppy disks.
Available with parallel port, SCSI, USB, internal,
and PCMCIA connections.
Backup Considerations
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What backup media will you use?
Does the system give you the performance and
reliability you need?
Is the system flexible and easy to use?
In the event of a disaster, will the recovery be
complete?
How fast can the system be up and running again?
Tape Drive
How Tape Drives Work
1. 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.
2. Data is then dumped from RAM to the tape drive controller buffer as
memory fills.
3. The controller sends commands to the drive to start spooling the tape.
4. 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.
5. Data is sent from the controller to the read/write heads.
6. The tape is composed of parallel tracks. Data is written from the center out
toward 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.
The Grandfather Backup Method
Day-ending tape: 4 media sets for each day,
Monday through Friday, rotated every week.
Week-ending tape: 4 media sets for each
Friday of the month, rotated every month.
Month-ending tape: 12 media sets for
each month, rotated every year.
The Tower of Hanoi Backup Method
Day
1
2
Media Set
A
3
4
A
5
6
A
7
8
A
B
9
10
A
B
11
12
A
14
A
B
C
13
15
16
A
B
C
D
E
Media Set
Used Every
A
2 days
B
4 days
C
8 days
D&E
16 days alternating
between set D and E
Relative Time to Back Up Data
Amount of data
100%
50%
1
2
3
4
5
Full Backup
100%
Amount of data
Amount of data
100%
50%
1
2
3
Differential
4
5
50%
1
2
3
Incremental
4
5
Common Problems with Internal
Removable Media Devices
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If the computer case is not properly aligned with the
chassis, the opening for the internal drive might be
difficult to access.
Because there are large openings in the case for
these devices, it is common for them to gather large
amounts of dust, so be sure to keep them clean.
Be sure to properly store the media so it is not dirty
or damaged. Using dirty or damaged media can
damage the drive.