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You need to make sure your solution in such environments makes sense and provides a solid level of protection for your data without costing unreasonable amounts of money. Tape is the standard, reliable, non-work-intensive way to pull this off.

Size Matters

While small-business and SOHO requirements are somewhat different from those of larger enterprises, the data in these environments is no less valuable. Not uncommonly, the term "off-site storage" means the office manager is taking backup tapes home at night. Small companies and SOHO environments can turn to a variety of small, inexpensive tape backup drives to fill their needs; some companies, such as Hewlett-Packard Co. and Tecmar, offer drives that suit the needs of these environments perfectly.

Among the first things you must consider when selecting a tape backup drive is size. How much data will you put on the drive? You'll want to avoid having to change tapes; if manual intervention is required to change a tape, your chances of finishing backups on a regular basis decrease. For one thing, it's human nature to forget or ignore a daily repetitive task. Second, tape backups are commonly performed at night, during periods of low end-user activity, so it's likely that no one will be around to change a tape if the need arises.

The easiest way to ensure complete backups is to buy a tape drive with the capacity to back up all your data on one tape. Other important factors are speed, compatibility with your software and price.

A Bewildering Array

Several nontraditional forms of backup -- CD-R, Zip and ORB removable media -- get a lot of press. A CD-R solution is fine for permanent storage or for creating libraries of material, but a CD-R's capacity is only 650 MB for 74-minute media and 700 MB for 80-minute media; that won't cover most enterprises' backup needs. Castlewood Systems' ORB drives offer 2.2 GB of space, but that's still probably not enough to do a full system backup. And at only 250 MB, Iomega Corp.'s Zip drive certainly isn't adequate.

The bottom line: Tape drives are a low-cost, reliable solution for your SOHO or remote environment.

One viable low-end tape solution is Travan, a QIC (Quarter-Inch Cartridge) technology from Imation Corp. (spun off from 3M Corp. in 1996). Travan cartridges are inexpensive and pervasive, widely available in consumer-electronics stores. Companies that produce Travan drives include Compaq Computer Corp., HP, IBM, Seagate Technology and Tecmar. Travan devices deliver up to 20 GB of compressed capacity (10 GB native), and come in IDE, SCSI, USB and parallel-port versions. Data-transfer rates for the IDE and SCSI versions are about 60 MB per minute in native mode.

A good example of an efficient, low-cost Travan device is HP's 14-GB Colorado tape drive, which is priced at less than $300 and comes with versatile backup software. One feature that keeps the cost down on this drive is its IDE interface. While IDE is slower and less capable than SCSI, the use of an IDE interface takes the cost of SCSI integration off the drive and the cost of a host adapter off the server or client.

This type of solution works very well as an addition to an office manager's or network manager's workstation, letting backups be performed from that location. Another advantage is the relatively inexpensive media, with a 14-GB Colorado cartridge priced at less than $40.

For greater data storage needs, you can step up to the next rung: DDS DAT (Digital Data Storage Digital Audio Tape). In this technology, which is more expensive than Travan, the cartridge is physically much smaller but its capacity is larger. DAT was originally created for audio enthusiasts. Its appeal for the manufacturer is the use of helical-scan components, which became cheap and common during the explosion of VCRs in the 1980s. When opposition to the DAT standard from such august bodies as the RIAA (Recording Industry Association of America) became too much in the home-audio arena, Sony and other creators of DAT put it to use for computer data applications. As an example of this type of solution, Tecmar's TS9400 DDS-4 DAT drive provides a 40-GB compressed capacity (20 GB native) for around $1,000. Transfer rates are about 165 MB per minute in native mode. Drives such as this generally are offered only in a SCSI version.

A close cousin to DAT is AIT (Advanced Intelligent Tape), developed by Sony. This variant on the DAT standard uses similar internal components but higher-capacity media. AIT comes in two flavors, AIT-1 and the more recent AIT-2, the latter offering increased capacity and twice the speed of the earlier generation. Both versions are still shipping. AIT drives use an 8-mm tape technology called AME (Advanced Metal Evaporated): The tape is coated with a very smooth diamond-like substance, which gives the tape a high resistance to wear while simultaneously reducing wear on the heads. AIT-1 drives can hold up to 35 GB in native format, with a transfer rate of 180 MB per minute. Sony sells its SDX-300c internal SCSI drive for about $1,350.

If your data-backup requirements exceed 40 GB, you'll need to look at some of the higher-end technologies typically associated with autoloader systems. (For more information on automatic cartridge-loading systems, see "Buyer's Guide: Tape Autoloaders.") Autoloader devices are available in single- or multiple-drive format. One type of autoloader uses the DLT (Digital Linear Tape) technology, which was originally developed by Digital Equipment Corp. and later sold to Quantum Corp. DLT drives are currently sold by ADIC, Compaq, HP, IBM, Quantum and others. This technology offers up to 40 GB of native storage and transfer rates of 180 MB per minute in native mode. HP's SureStore DLT1i internal tape drive will cost you approximately $1,450.

Another tape system to consider is Exabyte Corp.'s Mammoth tape drive, a helical-scan system on an 8-mm tape that offers 20 GB of native capacity (40 GB compressed), with transfer rates of 180 MB per minute in native mode. The Mammoth drive is available in several SCSI versions; Exabyte's EXB-8900SLCDi, an internal, narrow SCSI drive, runs about $2,050.

Other technologies can accommodate even more data; for example, Exabyte's Mammoth-2 tape system offers 60 GB of native capacity. Priced at around $4,000 per drive, however, such devices are a touch on the expensive side for the small-business environment.

If your data-storage requirements are modest and you've acquired a Travan drive, you probably already have some type of backup software. If you purchase any of the higher-capacity drives, though, you'll need to buy software to run them.

Computer Associates International, Legato Systems, Veritas Software and other companies sell high-end backup-software solutions for the enterprise, but these products can cost as much as the drives themselves. An alternate solution to consider is Retrospect Server Backup from Dantz Software; at about $500, this could be the ideal package for you.

If you are running a Unix system, you should check out Backup Central (www.backupcentral.com); this site offers several freeware and open-source backup programs, such as AMANDA (the Advanced Maryland Automated Network Disk Archiver), and it will even help you learn to use the software.

Whatever program you choose, make sure it's compatible with your current tape drive or the one you intend to purchase. Most backup-software vendors offer trial versions of their products; we strongly recommend downloading the trial version and giving it a whirl. If the software has received good reviews and works with your tape drive, it may suit your needs. First and foremost, though, make sure the program is reliable and that you're comfortable using it; if it's too complicated, your willingness to do the necessary backup testing will be affected (see "Testing Your Backups").

Planning Makes Perfect

Here are a few things to think about when planning your backups: First, backups should be performed in periods of low server activity. The backup process will slow your server down considerably, so daytime backups are not recommended. Next, decide where to place the backup device itself. Do you want it on the server, or can you back up from a workstation and stream the data across your LAN infrastructure? If you're installing an IDE backup device, we recommend that you back up from a workstation. Typically, your server will use some version of SCSI; such a machine may not have an IDE interface -- or if it does, that interface might be disabled. If using one of the larger, faster, SCSI-only backup devices, it makes more sense to add the device to the server rather than add SCSI capability to a workstation. Finally, consider off-site storage of a complete system backup, performed at least once a week. If your enterprise can't justify a service to facilitate this, then have someone take a complete backup home each week. That may not sound terribly professional, but it will save you if a building disaster should occur.