From the Tech Vault Dept.: Another of those mystery pieces that leap into my lap from time to time, in this case as I searched for something else in the depths of my computer archives. I would say this dates from about 2002, but I’m not going to go nuts finding out if it ever was published or not and if so, where. It’s about a technology that had its day, and caused a bunch of those oddball backup tapes to accumulate until the hardware went bad and orphaned my data.
THE CENTURY TURNED, the lights stayed on. Your computer shrugged off the date change and you’re going to be sipping bottled water for a long, long time. How about backing up your data now?
Until you lose a hard drive.
The question, as one backup software developer once put it, isn’t if your hard drive is going to fail – it’s when. You don’t get much warning, if any. And when it happens, you’ll enjoy an unbelievably sickening feeling as you realize just how much data – data you need! – was sitting on that hard drive.
While researching this piece, I came across an Internet site that purports to answer your questions about just about anything. One of the pages dealing with data backup suggested that complete coverage may be unnecessary: “If you're willing to give the restore process a few hours, you can always restore your computer from original software installation disks or CDs.” Bad advice, as far as I’m concerned. Like having your underwear drawer ransacked, you don’t realize how unique your installation was until it’s messed up.
Back in the halcyon days when a 10 megabyte (Mb) hard drive was a voluminous luxury, you could back up data to floppy disks either by copying it file by file or using one of the available software programs to organize and catalogue the data as it copied. Hard drives grew. Floppy-based backups became unwieldy.
Those who could afford the extra hardware used extra hard drives, one mirroring the data on the other, and this remains the best backup strategy for large corporate networks. For smaller offices, a good option is digital audio tape (DAT), which is more reliable under heavy use and moves the data more quickly, but the drives are much more expensive – a 20 gigabyte (Gb, equal to 1,000 Mb) model costs around $800 – and more complicated to set up, because they require a SCSI interface. That stands for small computer systems interface, and it was the once-upon-a-time solution to the problems adding lots of peripherals while achieving fast data transfer rates. You have to add a special card to your machine and worry through the attendant headaches of interrupt requests and memory addresses.
For ease of use and cost-effectiveness, I prefer compact discs and quarter-inch tape. My home network is made up of three computers, with a total storage capacity of 25 Gb. My backup style is to run a complete backup of those machines once a month, and to back up what’s changed since then every night.
Recordable compact discs come in two forms: write once (CD-R) and rewritable (CD-RW), both of which hold 650 Mb. Recordable drives (CD burners) cost $200 or less and the CD-Rs can be had for less than a buck apiece, with the cheapest CD-RW discs about $5. Very cost effective, especially if you use the strategy of making a complete backup onto CD-Rs, and then keep an incremental backup going on a couple of CD-RW discs.
Quarter-inch tape (QIC) debuted in a format slightly smaller than an audio cassette; five years ago, 3M introduced the Travan tape, which boasted more storage capacity in a slightly larger package that still fit in the old QIC drives. And those drives aren’t much larger than a floppy disk drive and can fit right in the computer case.
As hard drives grew, so did the QIC format. Travan cartridges pushed into the gigabyte range, with the current version, the TR-5, holding 10 Gb. With software compression, you’re supposed to get up to 20 Gb on a tape, but that’s one of those phenomena that only occur in advertising claims.
I’m pushing about 15 Gb of full-backup info right now, which would require 15 to 23 CDs, depending on how much data compression I could achieve. So the new Travan drive is ideal. I tested a Seagate Hornet 20, sold in a package called TapeStor Travan 20 that includes a tape and all needed hardware to install the drive. It claims a swift 120 Mb per minute data transfer rate, which still makes for a lengthy process when you’ve got gigabytes’ worth to store. The package also includes Veritas Backup Exec, a program originally owned by Seagate and familiar to Windows users in a stripped-down version called Microsoft Backup. In an annoying configuration move, the Microsoft version couldn’t be set to run backups automatically. Happily, the Veritas version can, and although you can work at your computer while it’s backing up, it’s always most convenient to run those backups while you sleep.
Backup Exec lets you configure and save different types of backup – complete, incremental, differential – along with compression and verification options. And you can choose which files to include or keep out of the backup set. There’s a tiny piece of information included with every file on your hard drive called the archive bit, which simply asserts that a file has been written to the disk. Backup software turns off that archive bit once a file has been stored, which is how an incremental backup can identify only those files that have been added or changed since the last complete backup session. Incremental backups also turn off the archive bits; differential backups don’t, and so maintain a complete picture of what’s happened on your hard drive since that last full backup.
(What followed was company and pricing information, none of which is now accessible. So this is it!)
– Probably sometime in 2002.
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