Choosing a tape backup drive can be a simple job if you need to back up a single standalone system with a relatively small hard drive. The decision becomes more complex if the system has a larger hard drive or if you must back up a desktop system as well as a laptop. Choosing a tape backup drive type can be an even more complex program if you must back up a network server's hard drives and perhaps even back up the workstations from the server. As you ponder which backup tape drive you should select, consider the following factors:

• The amount of data you must back up
• The interfaces your equipment supports
• The data throughput you need
• The tape standard that is best for your needs
• The cost of the drive and tapes
• The capabilities and compatibility of the included driver and backup software
• Support for disaster recovery

By balancing the considerations of price, capacity, throughput, compatibility, and tape standard, you can find a tape drive that best meets your needs.

Note

When purchasing a tape backup drive, take the time to look through magazines in which dealers or distributors advertise. Several publications specialize in PCs and carry advertising from many hardware and software distributors. I recommend publications such as Computer Reseller News and Computer Shopper. CNet's online shopping service (http://shopper.cnet.com) can help you locate multiple sources for both popular and rare items quickly.

These publications cater to people or companies willing to go around the middlemen and buy direct. By reading such publications, you can get an excellent idea of the drives available and the price you can expect to pay.

While reading about drive capabilities and prices, don't neglect to read reviews of the software included with each drive. Verify that the software capabilities match your expectations and needs. This is especially important if you intend to use the drive on a nonWindows system because most backup software today is tailored for Windows. If you are not satisfied with the backup software included with a backup drive, check with the vendor to see whether a bare drive (no software) is available; then check with your preferred backup software vendor to verify that the drive you prefer is supported.

Capacity

The first rule for selecting a tape backup drive is to buy a drive with a capacity large enough for your needs, both now and for the foreseeable future. The ideal is to buy a drive with enough capacity so you can start your backup software, insert a blank tape in the drive, walk away from the system, and find the backup completed when you return. Because tape backups are generally rated by their maximum (2:1 compression) capacitieswhich is seldom reached in practiceyou should calculate the "true" size of a tape backup drive by multiplying the native (noncompressed) capacity of a drive by 1.5 (equal to rating the drive as 1.5:1 compression). Thus, a so-called "20GB" tape backup might be better described as having a "15GB" capacity (10GB uncompressed times 1.5). Of course, the compressed capacity of a drive depends on the backup software you use, the settings you use, and the type of data you back up. Already compressed data, such as Zip archives, JPEG and GIF, and some types of TIFF graphics files, can't be compressed further, whereas text and database files can be compressed significantly. If you find that you have higher or lower compression ratios during backup, use the compression ratio you normally achieve to help estimate your true backup capacity.

You should always ensure that your tape backup medium supports a capacity larger than your largest single drive or partition. This makes automated backups possible because you won't have to change a tape in the middle of a backup. And, even if you don't mind replacing tapes in the middle of a backup, a single-tape backup is safer. If the first tape of a multiple-tape backup is damaged or lost, the entire backup is unusable with most backup systems!

Tape Standards and Compatibility

The next most important consideration, after adequate capacity, is choosing a drive whose tapes meet a standard that is useful to you. If you have existing tapes you want to restore, or you receive tapes from other users that you must read, you need a drive that can work with those tapes. Use the backward compatibility information listed earlier to help you decide on a drive to purchase if this feature is important to you.

If your ability to work with older tape media is only an occasional issue, you might prefer to buy a high-performance drive for current backups and maintain an older drive that matches the older standard.

Software Compatibility

Equally important to your consideration is the software required to operate each drive. Currently, most ATA drives come with software that runs under Windows operating system versions from 98 to XP. SCSI tape drives usually also support Windows NT, Windows 2000/XP, Linux, or various versions of UNIX. USB-based drives are primarily designed for Windows 98/Me/2000/XP. Check the manufacturers' websites for operating system compliance if your office's computers use more than one operating system.

Most operating systems have their own software for backing up data to a tape drive. If you intend to use this software, you should verify that the drive you purchase is supported by each piece of software on each system you intend to use with the drive. Third-party programs usually offer more features, but you might need to buy separate programs for the various operating systems your office uses.

Data Throughput

Any of the ATA, IEEE 1394a, Hi-Speed USB, or SCSI interface drives covered earlier should provide adequate performance (1MBps or above when backing up compressed data), but performance suffers if you opt for the convenience of USB 1.1 drives.

Cost

You can figure the cost per GB for a drive in two ways: media cost only or drive plus media costs (which is a better method for new purchasers). Regardless of your favorite choice(s) in removable storage, be sure to look at the total picture, taking into account the savings from multipack data and the benefits of the extra speed of SCSI and ATA.

Tip

One point worth remembering when you evaluate whether to buy a tape drive is that the cost of the tapes and drive, taken as a whole, is nowhere near as high as the costs (in terms of frustration and lost productivity) of a single data-damaging hard drive problem. Considering that most people are more likely to back up a system if they have a tape drive installed than if they must use another medium for the backup, the cost of a drive and tapes is quite small, even on a standalone PC used mostly for fun.

Support for Disaster Recovery

Disaster recovery, which enables you to create a tape backup and floppy disk set that can be used to reinstall an entire operating system and data file set without installing Windows first, is a function of both the backup software and the drive interface. Disaster recovery is supported with most backup programs.