Computer backups checklist.

Accidents happen. so do hurricanes, earthquakes, floods, fires and even acts of sabotage. Any one of these events can wipe out a business's computer information system. While there are expensive wasy to safeguard data, none is cheaper or easier than a tape backup system, in which all computer data are copied onto a magnetic tape. This checklist outlines the dos and don'ts.

* Make full backups. Most tape backup systems can, if the user wishes, back up only files that have changed since the last backup. While doing so appears to save time, it's not as efficient as backing up all files regardless of whether they changed because the restoration process is more cumbersome and time-consuming. For example, if a hard drive must be restored, every tape since the last full backup must be restored to reproduce every file.

* Don't just back up data files; make sure application programs also are backed up. Many people do not back up application programs because the original disks still are available. However, it takes time to reinstall and reconfigure a program--especially customizable programs such as word processors, spreadsheets and databases.

* Use the verify option. Almost all tape backup systems can verify that the data written to a tape are exactly the same as the original data. This generally is done automatically: The backup system copies the data and then repeats the process to verify the data. While doing so doubles the backup time, it can provide valuable additional assurance. If backups are done after office hours, the additional time probably is not an issue.

* Back up every day. Data should be backed up regularly. If the system is on a network, the file server probably is left on all of the time anyway, so it's best to program the server to do the job automatically. Virtually all tape backup systems allow for such automatic backups.

* Test the backups. When the time comes to use a backed-up tape, many companies have found there either are no data on it or the data are unusable. The only way to be certain that a backup procedure worked properly is to perform tests on a regular basis. If a backup requires more than one tape, make certain all the tapes are restorable. Keep in mind that just because a file is listed on a tape directory doesn't guarantee it actually is there.

* Use a single tape, if possible. Buy a tape backup system that can hold the entire hard drive(s) on one tape. Larger backup systems are expensive, but compared with the cost of reproducing lost data, their prices become relatively inexpensive. Another reason to use just one tape: Since there is no need to switch tapes, which is time-consuming, backup is less likely to be overlooked during busy times. If backup occurs automatically after business hours, there is no need to have someone present to change tapes.

However, if there is not enough room on one tape, choose some directories (such as program directories) to omit and then make a point of backing them up manually on a regular basis.

* Store backup tapes off site. For extra protection, consider storing the daily backup tapes at one location and the weekly backup tapes at a second location.

* Maintain a "boot" disk. If the computer has a complete hard disk failure, a "boot" disk--which is a clone of the computer's startup configuration and operating system--may save a great deal of time. A boot disk allows for recreating all the internal settings and disk files necessary to make the hardware operate properly. Without such a disk, the tape drive may not be restored easily. There are several popular utility programs that can create boot disks automatically: for example, Norton Utilities and PC Tools.

* Save some tapes permanently. A common practice is to permanently save all data every month. While this practice costs as much as the added tapes, the tapes that are generated often come in handy. For example, if someone wants an old file that he or she long since has erased, it's still available.

* Rotate new tapes. Keep introducing new tapes to the system, using the newest ones for the daily backups. Tapes have a limited life, so by constantly updating them, you reduce the chances of having a tape failure.

Adapted from a technology alert, Tape Backups May Not Be Enough, by Larry Wolfe, CPA, published by the American Institute of CPAs information technology membership section.