Data Storage "Best Practices" for end-users
Users often ask questions about storing and backing up their data, and we often find that some users haven't changed their data storage habits in years. With advances in technology, practices that were routine or even advisable years ago may no longer be the best way to guard against data loss. What follows is an introduction to different forms of storage, and some some guidelines for how you as an end user can help insure that you do not lose important data files.
Diskettes Are the Least Reliable Form of Data Storage
Did that get your attention? Good. We're entirely serious. If you are keeping your only copy of an important document on a single diskette, you're asking for trouble. If you are keeping copies on multiple diskettes, that's better, but it's still not the best way of protecting yourself. So, what is a diskette good for? Several things.
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In spite of the fact that the hard drive in your computer (or the network drives) are far more reliable than diskettes, things can go wrong. Diskettes are a cheap way of making a portable backup copy. In other words, save to your network drive (F:) or your hard drive, and then make a copy of the file on a diskette. That's assuming that whatever you're working on will fit on a 1.44MB diskette. Many Corel Presentations or Microsoft Powerpoint presentations wouldn't, for example. In cases like this, we'd recommend saving to a network drive and also to your hard drive and/or CD-R/CD-RW.
- A correctly-configured diskette can boot your computer in an emergency. Basic networking client software can be placed on them as well, which gives computer support personnel a good way to copy your data files from your hard drive to the network if there is a problem that is preventing Windows from starting.
Hard Drives
Hard drives are very reliable. The expected lifetime of most drives is at least an order of magnitude longer than it was a decade ago. Barring a power surge or a dropped computer, drive failures are relatively rare. That doesn't mean that due to a software error (from Windows itself, a device driver on the system or another third-party application) that the data on the drive can't be corrupted. If bad software (or a bad interaction between pieces of software) gives the drive controller valid commands to write bad data to the hard drive, it's going to pass them to the drive and perhaps damage the file system, causing you to lose files. The information about what files are where on the drive are just data, like the files themselves.
Even more likely is a computer virus, which could can also wipe out data on your hard drive. They can also damage or delete files on network drives to which you can write or from which you can delete data. (F:, G:, open directories on K:, etc.). We recommend you always install F-Prot anti-virus updates as they are presented through the Application Explorer when you log into the campus network.
Finally, failing to shut your computer down properly can increase the risk of data corruption on a drive.
We recommend you save data to your hard drive and to at least one other location (preferably to the network or CD-R/CD-RW, or to multiple diskettes). Hard drives don't fail often - between June of 2000 and June of 2001, we only had to send out about 60 computers to have the hard drives replaced, including all faculty, staff, student and lab/public PCs -- about 3% of the total number of systems. Frequently-used diskettes will likely fail in a few years, a substantially higher rate than 3%. Even under ideal archival conditions (controlled temperature and humidity, infrequent use, etc.) a 3.5" diskette does not have a long expected life span.
Network
Everyone on campus can save data to their own personal drive space (usually mapped as drive F: once you log in). Faculty and staff (and some student employees) have departmental storage space which is usually mapped to drive G:. Some campus organizations have storage space as well. Finally, faculty and anyone enrolled in one or more courses have directories corresponding to classes being taught or taken on drive K:. Files on the network can be accessed by the standard Novell client software from a PC on campus, or via Netstorage from off-campus.
Even if you have a file saved to the network, if you leave WordPerfect, Word, Quattro Pro, Excel, etc. running with that document open overnight, that document will not be backed up. Also, if you do not save your document, spreadsheet, data, etc. and we need to do server maintenance (or if a server crashes) and it causes your PC to crash, you could lose the unsaved work. Please save your work and shut down your computer when you go home for the night.
Your personal network space is just that - yours. Unless you grant others specific rights, standard users cannot access those files. The drive array technology used to store network data is extremely reliable, and we do perform regular backups of network data. However, there are some limitations to the reach of network backups - mostly logistical in nature. The most important thing to remember is the warning above about saving your work and exiting from the application.
Shared departmental/organizational space is more complicated. Generally, everyone in your department or group has equal access, so what one employee or member places there another can remove. For this reason, we recommend that any important documents you plan on placing in your departmental/organizational drive space also exist in at least one other location, such as your own personal network space, on a hard drive, or on CD-R/CD-RW.
If the instructor of a class has set up a shared work area in a course's K: drive directory (unlike the default Inbox/Outbox behavior, where a specific student has some rights to a given directory, and only the instructor has full rights to all directories), that shared directory is likely vulnerable in the same way the shared departmental drives are. Again, we recommend making an extra copy of the work to at least one other location -- such as your own personal network space, on your hard drive, or on CD-ROM/CD-RW.
There is the ability to "Salvage" or rescue recently-deleted network files. However, if you don't realize that you (or another user on a shared network space) deleted the file for some time, it may not be possible to reprieve the file before it is purged by the system to make way for new data.
CD-R/CD-RW
While writeable CD-ROMs (CD-R) drives have been around for a while, in recent years support for rewritable (CD-RW) discs has been added, and the drives are considerably faster. At the same time, prices have come down, making them very attractive. In addition to the Compaq Armada e500 model issued to entering students in 2001-2002, There are currently two labs in the Helpdesk - room 7 and the Multimedia Lab (room 13) equipped with CD-RW drives for public use. The Language Resource Center in Brothers College can support UDF/DirectCD formatted CD-RW discs as well. While the section below may seem a bit confusing, in practice it's really quite simple. CD-R media can be used to create a standard CD-ROM, and CD-RW media can be used either as an erasable CD-ROM (with limited compatibility) or as a removable hard drive/very big diskette.
CD-ROM formats
CD-R media cannot be erased, but if created as a "multi session" CD-ROM you can add additional files and folders to it. CD-R media can normally be read in any CD-ROM drive. The typical CD-R/CD-ROM format is referred to by slightly names depending on the utility used to create the CD-R. Either "ISO 9660" or "Joliet" are commonly used formats, the main difference being that "Joliet" can support file names longer than the old MS-DOS "eight plus three characters" convention.
CD-RW (rewritable) discs that are formatted as standard "ISO 9660" or "Joliet" formats (like typical CD-ROM) can be read in newer CD-ROM drives without additional software, and have the added advantage of being erasable so that you can reuse the entire disc. Older CD-ROM drives, which includes those in most campus desktops, cannot physically read CD-RW discs no matter the format, due to differences between CD-ROM/CD-R media they were built to read and the CD-RW discs. The CD-ROM drives found in the more recent notebook computers (the Acer Travelmate 512T and Compaq Armada e500) can read ISO 9660/Joliet formatted CD-RWs without additional software.
CD-RW/UDF formats
The most flexible format for CD-RW use is something called "UDF," usually written to a CD-RW disc with a program called "DirectCD." Most CD-RW drives come with the Adaptec/Roxio DirectCD software. DirectCD allows you to format a CD-RW disc as "UDF" media and then use it like a 500+ megabyte removable floppy or hard drive. You can copy files to it, delete files, move them, etc. This is one of the most convenient ways to make backup copies available today. With an additional free utility, newer CD-ROM drives can read from (but not write to) CD-RW drives formatted as UDF media with DirectCD. This has been successfully tested with the Acer Travelmate 512T and Compaq Armada e500 notebooks. The Compaq Armada systems with CD-RW drives (the system provided to the 2001-2002 entering class) do not need this utility.
Zip Drives
We're sometimes asked about Zip disks. The 100/200 megabyte Iomega Zip drives are a fairly old technology, and share many of the same problems as diskettes. In Academic Technology, we have been phasing out Zip drives in favor of CD-R/CD-RW drives and network storage for some time. We have seen both failing drives damaging Zip disks, and bad Zip disks damaging Zip drives. Steve Gibson's web site has more information about Zip drive issues at the bottom of the page. Zip disks are quite a bit more expensive than CD-R/CD-RW disks and store less information. Finally, since a CD-R (and, given the limitations outlined above, a CD-RW) disc can be read in any CD-ROM-drive-equipped computer, they're a far more universal format than Zip disks. All newer computers have CD-ROM drives, and the writeable CD-R/CD-RW drives are rapidly spreading in the computer industry as well. If you wish to transfer data from 100 megabyte Zip disks (we do not have 250 megabyte Zip drives) to CD-ROM, the computers in Room 7 in the Helpdesk are equipped with both Zip drives and CD-RW drives. Newer "Zip" drives are only slightly higher capacity than a CD-R/CD-RW, and are considerably more expensive.
Removable Hard Drives and DVD-R/-RW/+RW
Various vendors make removable hard drives in cartridge form, much like Iomega's now-discontinued Jaz drives. While some of these work quite well, are fast and are high-capacity (some as high as 20 gigabytes or more), they also have limitations. For some you need specialized hardware or software, and can be quite expensive. Not only for the drive hardware itself, but for each cartridge/removable drive.
We expect that writable DVD-ROM discs (DVD-R) and one of the two Rewritable DVD specifications (DVD-RW or DVD+RW) will end up eclipsing removable drives, because, like CD-ROM drives, there will eventually be a drive able to read the discs in most computers. Also, the cost per gigabyte will be considerably lower for writable DVDs, much as the cost per megabyte currently is low for writable CD-ROM media. However, for specialized needs - for example, professional video production where both high capacity and how quickly the device can write the information out to the drive matter, these devices will likely remain popular. We don't expect the standards argument over DVD storage formats to be settled soon, and until then, either of the two rewritable DVD specifications (-RW and +RW) could fail in the marketplace. Lack of a single rewritable standard will likely slow the adoption of writable DVD media.
Don't Forget the Lowly Printout
While we do want to encourage people to conserve paper, a paper backup has some advantages. Most people don't need a computer, a particular software application, or even a particular type of data storage device to read it. We strongly recommend users writing a thesis or dissertation also make printouts. If it's a long enough document to take too much time to retype, you can always use optical character recognition software to scan it back into a computer. The Helpdesk does offer a fee-based scanning service. While not perfect (page numbering, footnoting and other formatting may have to be redone), a good quality printout can generally be scanned fairly accurately.