The Missing Gigabytes problem
Here's an example of a query which keeps appearing in the Freecom Forum, the answer to which is well-known amongst computer "enthusiasts" but which is much less known to the average computer user.
"I bought a freecom 400G external hard drive from PC world. It is windows preformatted- however, on installing it on my machine, there is only 372GB available- is this usual? Where is my missing 28GB"
The answer is, yes, it's perfectly normal. Drive manufacturers usually describe their products using a fairly common "mistake" that a Gigabyte equals one thousand million bytes (a thousand megabytes). The actual value of a Gigabyte is 1,073,741,824 bytes (1024 megabytes). So the manufaturer describes the drive as "400 Gigabytes", whereas your operating system correctly calculates the actual amount of Gigabytes at the 372GB figure. It's a well-known problem! OK - the manufacturers should really be pulled up for wrongly describing their product but they've been doing it for many years - in the days when drives were maybe 8megabytes (yes, they really were that size once....) the "missing" megabytes were so few it did not really matter. But now that we have 500GB drives as the norm, people have started to notice the "missing" storage space. Will it ever change.....who knows!
NTFS and FAT32
There are frequently queries in the Freecom Forum about filesystems, with "FAT32" and "NTFS" being the main areas of confusion. I won't bore you with the full history of these systems - if you want that, go google and be prepared to spend some time reading about them. It's enough to say that, in the days of MS-DOS, that operating system needed a means by which the file space on a hard drive could be logically managed and "FAT" (File Allocation Tables") were created as the means of managing each partition on a drive. Later, computers and operating systems became more powerful and, with the introduction of Windows 95, an improved version - FAT32, became an option. Still later again, Windows NT (and all Windows systems from Windows 2000 onwards) adopted NTFS (Windows New Technology File System) as the standard, although all these later systems could also handle FAT32 partitions.
Which is "best"? Well, that depends on what you are doing. In a situation where you use only 1 computer, with an operating system of Windows 2000 or newer, NTFS offers a number of significant advantages. However, NTFS, because it has improved security features, is deliberately less "accessible" to other operating systems than FAT32. So if you plan to use, say, a network, with another PC which has a system older than Windows 2000, you have to have at least one partition of FAT32 on the PC with the newer OS, and only the data stored on that partition will be available to the older operating system. Almost every operating system can access FAT partitions, quite a number (including Linux, MAC, and OSX) can access FAT32 partitions, but only Windows systems of Windows 2000 or newer can access NTFS partitions (there are some software utilities which can pretty much get round the problem of these other systems getting access to NTFS but that's a farily complicated area, beyond the scope of this simple explanation).
FAT32 and the 4GB limitation problem
So - why not just use FAT32 so that all your devices can access such partitions? Well,the main problem is that FAT32 can only handle individual file sizes of less than 4GB - if a particular file is larger, it can't write it to disk. "OK then", I hear you say, "I'll just use NTFS to get round that problem". But, unfortunately, using NTFS will mean your netorked devices can't access that partition. So - what to do?
Two solutions! First - don't use any files larger than 4GB! OK - just joking - not really practical in these days when a single DVD video file can easily exceed 4GB. Also, if your backup programme is a bit short on functionality, it is likely to create a single backup file of all your files, which certainly will exceed 4GB. So, that's not a realistic solution.
The alternative - file compression. You've all heard of WinZip? If not, in very simple terms, a file compression programme (WinZip is only one example - there's lots of others) does what it says on the label - it "compresses" the file so that it becomes smaller - if you're lucky, it will compress it sufficiently so that the eventual file size is less than 4GB. If, after compression, the file still exceeds the 4GB limit, there's another trick up the compression programme's sleeve - file splitting. Again, it does exactly what is says on the label - it takes the file and splits it in to a number of smaller files, each less than the 4GB limit. When you uncompress the file for use, it assembles everything back together, as if it were again one file. Later Windows systems have their own file compression system built-in and you should find that you can compress files in a very simple operation. A good compression programme will do all this almost without you being aware of it.
Backups to a Network Drive
Finally - a brief word on backups and backup programmes. A good-quality backup programme should be able to automatically carry out the file splitting routine so that you can backup your entire system to a FAT32 partition without difficulty. I'm not recommending it (I've never needed any backup programme beyond the built-in Windows backup programme) but Acronis is at least one software supplier who does offer a backup system capable of file splitting (and there are lots of others). And remember the golden rule - a backup is exactly that - it's only a backup of the original files which are held elsewhere. Here's an example of what I'm getting at:
"I backed up all my important files to my network drive, it's stopped working and I've lost all my files. What can I do"
That's an example of a query I often see on the Freecom Forum. It tells me that user does not understand what a backup is. At the risk of boring some of you, here's the detailed explanation.
In this case, the user has NOT backed up (ie - copied) his files to the network drive - he has moved them. If he had copied the files and his network drive fails, he would still be able to access all his files on his PC and only the copies would have been lost - no big deal. But, because he has moved the files, if the network drive fails, all is lost (well, maybe not - see my other pages on Data Recovery for further help).
So - a backup is a copy of the original files, which should be held elsewhere - certainly on another device (eg, your PC) and, ideally, in a different room - better still in a different building - from the network drive (in case of serious fire or flood or other real disaster). And don't forget you need to make backups as often as you add new files or amend old ones.
As they say in Scotland - you've been telt!
Network Drives
These drives - not just Freecom's, but other manufacturer's as well - normally are supplied formatted in FAT32, to be accessible to as many differing types of operating system as possible. Without going in to explanations for it, most of these drives (possibly all at present?) aimed at the "average consumer" end of the market, will use a built-in Linux-based system to handle the drive's networking operation. And Linux, (or at least the Linux versions used in network drives) as you will have gathered if you read the bit above, can't handle NTFS partitions (well, not directly). So, while you CAN re-format your network drive with NTFS, you won't then be able to use it as a proper network drive, although you will be able to use it on a USB connection if your drive offers that facility. But, provided you use the aforementioned file compression/file splitting utilities, you will be able to happily use your FAT32 network drive for the purposes intended when you bought it!
Any further queries, or any bits you disagree with or think I've got wrong? If so, please post on the Freecom Forum, with "techie" in the title and I'll try to respond.
The Techie from Sneckie
4 September 2007