Time for backup

Sng Chee Khiang / Singapore

Computers have become so essential in businesses nowadays that companies are likely to suffer heavy losses if their systems were to break down. More important than the computers themselves, is the crucial business data in their storage systems.

Many users can attest to computers experiencing problems at an alarming rate. If it is not a software failure caused by virus attacks, then it is usually a hard disk crash that destroys all the data on it.

And hard disk failures usually happen when you least expect it, prompting the often-heard comment that “it is not if your hard disk will fail, it is when”. Other potential dangers include the threat of natural disasters such as fires and floods, as well as human error.

But with the myriad array of backup methods and technologies out there in the market, which one should small-and medium-sized businesses (SMBs) be looking at to backup their critical data?

Essentially, the difference between the backup methods is the device and medium that is used to store the backup. Different media have different characteristics, such as capacity, speed, and ease-of-use, but in reality, the amount of data to be stored is usually the determining factor.

ACW delved into the market and found the following backup options (under $5,000) for SMBs.

Removable storage devices

Removable storage devices such as mini USB drives are gaining in popularity. Their capacities range from 16MB to 2GB, and they come in form factors the size of key chains to a pack of chewing gum. Weighing virtually nothing, these mini USB drives cost anywhere from $10 to $400.

Such devices use flash memory chips, which can be erased and reused as needed. They are easy to use—just plug the drive into the computer’s USB port and the computer will recognise it and assign it a drive name. Then just click and drag the files you want to back up to the mini USB drive, and you will have instant access to your backup files wherever you go.

There are also the large floppy disk equivalent drives such as the Iomega Zip drive, Syquest’s EZ-135 and the LS-120. Such disks have capacities ranging from 100MB to 750MB, and prices for the drives range from $50 to $180. The media cost between $6 and $11 each.

CD/DVD

CDs and DVDs have been around for quite a while now, and are one of the more popular methods for backup, as the ROM drives can be found on almost every computer.

They are seen as a general purpose medium because of their flexibility—the re-writable CDs and DVDs are reusable for about 1,000 times and can usually be read by any other CD or DVD drive.

The capacity of CD/DVD media range from 650MB to 4.5GB, and new double-layer DVD media comes with 8.5GB capacity. These are priced from $0.30 to $2 a disc. The drives are priced between $50 and $250, and they come in both internal and external forms.

Hard disk drives

It may seem ironic to use another hard disk to back up your main hard disk, considering that the backup is prone to similar failure.

But having a backup is better than none, and the prices per gigabyte of hard disks nowadays are very comparable to other backup options—and in some cases may even be cheaper.

Users can also buy an external drive bay to convert their hard disk drives into portable storage. Other advantages of using hard disk drives as backup include high performance, standard interfaces and exchangeability.

There are also vendor-specific removable hard disk drives, such as those from Maxtor, Iomega, LaCie, and these are typically bigger in capacity than internal hard disk drives. Their advantage lies in their plug-and-play ability, but you will have to pay a premium for that.

Hard disk drives come in sizes from 40GB to 300GB, and cost anywhere between $50 and $160. Vendor-specific removable hard disk drives have capacities ranging from 10GB to 1.6TB, and you can expect to pay $50 to $2,200 for them.

Tape drives

Tape drives used to be very popular, because you could replicate your entire hard disk’s data on them. But with the growing

capacities of hard disk drives, tape drives are not making headlines anymore. Far from conceding defeat, tape drive manufacturers have developed new tape drive technologies that vastly improve on storage capacity and backup speed. However, choosing the right tape technology to suit your business can be daunting as there are quite a number in the market—digital linear tape (DLT), Super DLT, advanced digital recording (ADR), Linear Tape Open (LTO) and VXA-2 are just some you will come across.

Data tape media have storage sizes ranging from 2GB to 1TB (without compression), and bigger capacities are expected to appear on the scene in the next few years. Tape drives start from $99, and the price of tape media starts from $25.

NAS/SAN

Network-attached storage (NAS) or a storage area network (SAN) may be an overkill for the average SMB looking for simple backup options, but with prices coming down, users should consider them if scalability is an issue. A NAS device is a server that is dedicated to file sharing, and allows more hard disk storage space to be added to a network without shutting the network down.

It can exist anywhere in a LAN and can be made up of multiple networked NAS devices. The storage capacity for a NAS device usually starts at 120GB, with pricing from $350.

On the other hand, a SAN is a high-speed sub-network of shared storage devices. Its architecture makes all storage devices available to all servers on a LAN or WAN. To reap the benefits of a SAN, a fibre channel backbone is recommended, although IP-based SANs are gaining in popularity as well.

Backup methods

In addition to getting a backup technology that suits the company, SMBs must also have the discipline to carry out the backup on a regular basis. There is no point in getting an expensive and feature-loaded backup system if you do not backup your data on a regular basis. With backup software as advanced as it is today, an automated backup solution can be a painless process with many organisations opting to do their backup after office hours without human intervention. This means that companies do not have to set aside several hours to perform a backup, and backups can be scheduled to automatically begin at regular intervals, according to ADIC, a backup systems vendor.

There are many automated backup software in the market, and some of the backup devices mentioned above even come with their own proprietary backup software.

A good backup and recovery strategy is also required. It will help protect data, reduce the backup window, enable more efficient storage usage and provide faster and more effective data recovery. According to HP, there are three ways in which backup can be performed: full backup, differential backup and incremental backup.

For full backup, all data on a system is replicated. They are usually done periodically to ensure that all data resides on a single piece or a single set of media so that in the event of information restoration, only the full backup media is required.

A differential backup stores all files that have changed since the last full backup. When restoring differential backup, the full backup media and the latest differential media are used. An incremental backup stores all files that have changes since the last backup. When restoring from incremental backup schemes, the last full backup plus all incremental backup sets are required.

HP also advised that data recovery procedures be rehearsed regularly so that companies can deploy swift and complete recovery from their backup tapes in the event of a disaster.

Doing a test restore on a regular basis also ensures that companies know how to follow the procedure and confirm that the backup technology is doing its job.

This article first appeared in Asia Computer Weekly