Face It, You're About To Lose Data

Face It, You're About To Lose Data
August 1993

Let's talk about disaster control. What will you do to minimize the effects to your business in the event of a computer disaster? If you don't think it could happen to you, don't bother reading further--you're probably not going to like what you read.

I promise you, if you use a computer system, you will lose data. If you've already lost files, I promise you'll lose files even more valuable than the previous ones.

Data loss will come from all sides. You may accidentally erase your customer list. Or worse, you may delete just a few customers and not realize it until days later. If you erase an entire data file, you can unerase it if you quickly realize what's happened. DOS versions 5 & 6, Norton Utilities, and PC-Tools all include unerase utilities.

However, if you unknowingly delete records from your customer database, your only recourse, short of retyping them, is restore the entire data file from a duplicate (backup) of the database file. To protect your data from loss, keep a duplicate set of all your vital files.

After you've made a duplicate copy of your computer files, take the copy off-site. An off-site copy of your data is insurance against theft, fire, and other threats to your information.

We use tape systems to backup our network data. Each morning, at 4:00 A.M., a 4mm Digital Audio Tape (DAT) machine copies all of our Columbia network files to tape. Last night, about 900 Mb of files were backed up. The tape will hold 4 Gb (4,000 Mb) of files, so we have some room to grow. The used tape is then moved to a safe, off-site storage location.

Each tape is reused every 30 days. We also keep a permanent copy of the network files as they were on the last day of each month. This way, a specific file that was created in January, but deleted a few months later, can be restored from the January 31st archive tape. A similar tape system is in operation at our Ellicott City office.

We have erased lots of important files; however, we've never lost any files permanently. By using "Unerase" utilities and backup tape copies, we've always been able to restore an erased file. (If you have a Novell NetWare local area network, you can also use the "Salvage" command to unerase files on the network files server.)

Most businesses prefer to use tape systems to backup large amounts of files; however, you can also use diskettes for smaller numbers of files.

Dozens of excellent backup software products are available to duplicate files onto diskettes. You have a handy backup program already installed in the C:\DOS directory of your hard disk. The DOS "Backup" command will copy and compress individual files or entire directories onto a series of diskettes. The DOS "Restore" command, the sibling to "Backup," will return the files to the hard disk in their original directory location.

Whatever backup system you choose, use it regularly.

How often should you backup your data files? This depends on how often your files are changed and how important they are to your business. We live by our network files; without them, we would practically be out of business. We backup at least once every day. On especially busy days, we also backup at lunch time.

If you use your computer to review tables of numeric data or customer lists, but only occasionally change the information, you only need to backup on the days that you make changes. If you've only made a few changes, you may opt to print the lists. The printed copy serves as a backup of your data. Then run your tape backup software less often.

Schedule emergency fire drills to test you backup procedures. Periodically, check your backup copies to make sure that your tapes and diskettes actually hold the data that you think they do! Your backup software may have an option to list the names of the files on the tape or diskettes.

Listing the files is a good start, but go one step further. Perform a restoration of the files and make sure they are properly restored. Retrieve them into your word processor or spreadsheet, whatever program you used to originally create them.

Remember, you will lose computer data! It's a matter of when, not if.

Your job is to minimize the effect of data loss by ensuring there's a viable duplicate of the data available. Good luck, see you again next month!

David Stephen Murphy is President and CEO of Damar Group, Ltd. which presents computer training classes, publishes computer learning guides, and helps organizations do business on the Internet. The website is http://dgl.com, and Mr. Murphy may be reached at dave@dgl.com or 410.567.5366.

updated November 2, 1996
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