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Re: [APML] OT: external HD questions
Here's the IT perspective.
All hard drives must be partitioned(1), but most of the time that means
simply one big partition encompassing the whole drive. Also, the
partitioning does not consume any more than about 1K of space, a
pittance. The filesystem consumes much more space, space needed to
properly database your files and folders.
At the factory, the manufacturer most likely set up a single partition
encompassing 100% of the available space, and preformatted this
partition with the FAT32 filesystem. This is for ease of use with
non-technical people. You can generally just plug it, drop files on it,
and fugetabowtit.
If you're technically minded, you can make some changes. I'd recommend
changing the filesystem from FAT32 to NTFS. It's not required, but
you'll gain some benefits.
NTFS has journalled file metadata(2). That jargon means it will handle
power interruptions and careless plugging and unplugging with more grace
and less chance of corrupted or lost data.
NTFS also supports a max filesize scads higher than the paltry 4GB max
size of FAT32 files. This may not mean much unless you're into video
work. Digital camera files, even raw ones, generally don't exceed 2GB in
a single file...yet.
To accomplish this filesystem change there are many ways, but might I
suggest using the Disk Management console. You can access it by
right-clicking on your My Computer icon, and choosing Properties. Then
click the Disk Management item from the left-hand pane.
This console is spiffy and allows you to view the partitioning structure
of your drives graphically. If you open the console with your drive
off/disconnected, then turn it on/connect it, you'll see it's partition
and volume data pop into existance in the window.
Right click the partition corresponding to your external drive and
choose Format. In the drop-down box for File System, choose NTFS. Click
OK. You can go back and forth like that, but of course, you're
formatting, so any existing data in that partition is going away in the
process. Experiment, learn, and have fun, then put it to work.
--footnotes--
(1) Strictly speaking, partitions need not exist on a hard drive to
store data. They must exist if you want to segment a drive's storage
capacity into multiple filesystem volumes. Your operating system may
also depend on them to properly work with the drive. Windows 2K/XP can't
make a filesystem and store data unless a partition exists. Linux,
however, is not limited by this. A filesystem can be created directly on
the drive, without a partition. The limitations are that you could not
boot your system from such a drive, and the filesystem will span the
whole drive.
Your memory cards are partitioned like hard drives too! Canon cameras
create a partition on the card, then format it FAT32. If you format the
card in the camera, this will happen. As an experiment, on my Linux PC I
took a card, removed its partition, and created a FAT32 filesystem
directly on the card. I then created some DCIM folders and dropped some
pix to it. Windows XP freaked out and called the card unformatted. To my
surprise, my Canon RebelXT and Powershot S410 both accepted the card,
could show the pix, and had no problem saving new pix. If I formatted
the card in one of the cameras, a partition was then created and
formatted FAT32.
(2) NTFS uses a special log called the journal, to keep track of write
operations in process. File metadata is first recorded to the journal,
then the operating system parses the journal and commits each change to
the filesystem. Only when a change has been completed, does the journal
entry get cleared. This way, if something bad should happen in the
middle of a write, the next time the filesystem is accessed the OS will
notice that the journal didn't get closed, the journalled change the
system was in the middle of writing will still be logged in the journal,
and the system can try again and, if successful, clear the entry and
move on.
Unfortunately with NTFS, only metadata is journalled, not the actual
data for a file write. The advantage is the filesystem stays consistent,
even if the data contained within a file is mangled. Fully journalled
filesystems like ReiserFS (correctly configured) and XFS are used on
servers where data integrity is preferred over performance. However,
it's better than FAT32 and related filesystems. Without any journalling
scheme, when crashes happen the filesystem can become inconsistent,
leading not just to garbled data, but mangled filenames, lost folders,
and crosslinks: where two different files or folders point to the same
data, even if they each had their own data before. Bad news. Think
Brendelfly!
(Perhaps more than you cared to know, but knowledge is power!)
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