Mon, 06 Mar 2000

Tape backup systems still play a vital role

By Zatni Arbi

JAKARTA (JP): What has the love affair between business and information technology (IT) brought us? Today we are swamped by data. It is now so easy to capture and collect data -- through Websites, through Point of Sales (POS) systems and through other online facilities.

Some of this data is legal, some is not. A lot of it actually belongs to the gray area. Case in point is the data collected by an Internet company called DoubleClick, which has been collecting data through five billion online ads that it serves. DoubleClick has been under forceful pressure from consumers and privacy advocates in the U.S. due to its plan to merge its data with the data on printed catalog consumers collected by Abacus Direct, a company with which it struck a deal for a US$1.7 billion merger late last year.

Black, white or gray, the volume of data collected since computers became widely used in business is really staggering. With the Web now becoming the source of music, video and broadcasting, in addition to the ordinary "passive" data like your identity and mine, the Internet has caused the data storage business explode, as testified to by the recent IPOs of several companies specializing in data storage.

However, if your business relies on data storage, you must also have a data backup system. Much like security, data backup should be part of your IT plan right from the outset. Current estimates say that there is a 3.5 percent probability a business will go bust if it ever suffers from a permanent loss of data. Today, we discuss some of technology that is available on the newest tape backup offered by HP, the SureStore DAT40x6 Autoloader.

Tape backup may seem to have disappeared into the background as people take the single QIC (Quarter Inch Cartridge) Colorado tape backup for granted. The fact is, new technology is still being introduced to tape backup products, making them a reliable solution for small, medium and even large enterprises.

For your home PC, however, investing in a tape backup would be overkill. A Zip drive, a CD-Writer or an account at @backup (a website where you can store your backup files) is sufficient.

Unattended backup

Small enterprises are usually defined as companies with less than 100 employees and no permanent IT manager who would ensure that backup of data has been properly performed, tapes are rotated correctly and the drive is clean and in good health. Therefore, what they would like to have is a backup system that manages itself, in addition to automatically creating backup from the primary storage of their server or servers. Automated backup is a must, because normal human beings simply hate having to get out of their bed in the wee hours to do the backup in the ever- shrinking backup window (in case you get a little curious, the backup window is a time span in which you can backup your data -- typically after the last person in your organization stops working at night and before the first person starts working the next morning). The SureStore DAT40x6 is a good example of the products that fit these requirements.

Launched at the beginning of last month, this DAT-based tape autoloader can be fed with up to six tape cartridges inserted into a magazine. The robotics inside the device will pick the correct cartridge and insert it into the DAT drive. The included TapeWare backup software will allow users to schedule automatic backup.

This tape backup device uses DDS-4 data storage specification. However, it is backward compatible, and can use DDS-3 and DDS-2 formats. It can read certain formats of DDS-1.

Like several of its CD-Writer, HP has also added a automated disaster recovery feature to the tape backup. So, in case the entire hard disk needs to be restored, for example after hardware crash and repair, the user will only need to press the Eject button, power up the device and then reboot the server. Because everything -- including a disaster recovery (DR) image -- has been backed up on the tape, there will be no need to reload the operating systems and applications from separate CDs or disks.

I found the One Button Disaster Recovery feature that HP has added to this DAT autoloader quite interesting. While Unix workstations can traditionally boot from a tape drive, the BIOS of a PC is not normally equipped with the capability to boot from a sequential storage system such as a tape (in a tape, data is stored sequentially -- one after the other).

So, as explained in the white paper that I got from HP, this feature has been added to make the tape drive work in a CD-ROM mode. Once the PC is tricked into believing the drive is a CD-ROM drive, the system can boot from it as if from a bootable CD-ROM, and everything -- operating system, applications and data -- can be restored. Once the restoration process is started, the system will reboot and the tape drive will assume its native mode.

Other features

As the tape itself may leave some particles on the drive's head, drive makers now add an automatic mechanism for cleaning it. HP does it by loading a cleaning tape at a scheduled time.

"Suppose you use one tape cartridge to backup your data on Monday, another for Tuesday and so on, you will use five different cartridges every week if your business runs from Monday to Friday," explained Lee Chin Keong, Commercial Business Manager of HP's AP Information Storage Group, "The sixth cartridge contains the cleaning tape." Cleaning can be done on Sundays, for example. The drive also has a sapphire blade that constantly touches the tape surface and sweeps all the tape debris away.

Everything that moves suffers from tear-and-wear, and a tape drive is no exception. The good thing about today's tape backup drives is that they are equipped with some intelligence that constantly measures the performance in real time and makes the necessary compensation to ensure the integrity of the backup data.

The tape backup market is still going strong. For high-end servers in large enterprises, the Digital Linear Tape (DLT) is the choice. DLT technology was first developed by Digital Equipment Corporation, which is now owned by Quantum. It provides not only larger storage capacity but also faster access time. While the DAT40x6 can transfer data at the rate of 6 MB/s (with 2:1 hardware compression) and can store up to 40 GB per tape cartridge (also with 2:1 hardware compression), HP's high-end DLT Autoloader 818 has a native transfer rate of 6 MB per second and offers a total of up to 320 GB of backup storage capacity.

Incidentally, if you happen to lose your mission-critical data despite all the backup systems that you have put in place, there may still be hope to get it back. DisTek ( is a U.S.-based company that can go to the physical level of your hard disk and retrieve it. DisTek claims a 95 percent success rate, which is really impressive. You will have to weigh the value of your lost data against the cost of retrieving it, of course.