Storage decision is no longer open and shut

By Linda Musthaler

When was the last time you gave much thought to your decision about primary storage solutions? Many companies don't consider it a decision at all - they simply use whatever storage resources come with the server they buy. Well, a few things are happening that should make you think about your storage choice.

First, Fibre Channel technology is becoming increasingly important. While Fibre Channel has been around for a few years, it is now more crucial than ever because of the growing popularity of server clustering, which necessitates the move from internal to external storage. The traditional method for connecting external storage to a server, SCSI, can support the clustering of at most two servers; Fibre Channel allows you to connect any number of servers to storage units.

Although a Fibre Channel-attached storage solution may cost more up front, it holds the promise of a lower overall cost of ownership over the lifetime of your system. This promise comes in the form of greater growth potential, expandability, reliability, speed and distances that can be served.

However, Fibre Channel connectivity is not without controversy. Some vendors have chosen to implement proprietary Fibre Channel solutions; other companies are pushing for industry standards. Even the advancement of standards was controversial for a time, with two different bodies working on them. The two joined forces, and the resulting Fibre Channel Loop Community now is the standards bearer.

Second, storage technology is changing rapidly, accompanied by an equally rapid drop in price. While users primary storage requirements are growing at an average rate of 40% per year, the storage density per drive is increasing at an average of 100% per year. Thus, we can fit more information in less space, reducing overall costs.

This is especially good news for server vendors such as Compaq, Dell, IBM, HP and Digital Equipment, which bundle internal storage with many of their server products. Because up to 50% of the price of a server can come from the storage component, these vendors can reduce prices on their servers while simultaneously offering higher capacity products. Most of these vendors also have announced storage strategies that include external Fibre Channel-attached storage for clustered servers.

Third, like other industries, the storage market is undergoing consolidation. The merger announced last month between Storage Dimensions and Artecon is a case in point.

Mergers are inevitable, given the evolutionary pace of storage technology. There are just too many specialty vendors that will have to close ranks to offer broader product lines to a burgeoning PC LAN market. This industry consolidation means you have to look more closely at the viability of your storage solution provider.

So now that you know why you should give some thought to your primary storage solution, let's look at your options. The choices basically come down to internal vs. external storage.

Internal storage usually refers to a RAID that is a physical component of your server. The storage component has most of the features necessary to make it virtually fail-safe, but it still depends on the server for cooling and power systems. The storage capacities of today's ser-vers are quite sufficient for many small businesses or departmental applications.

External storage is another box (or boxes) that takes directions from the server via software. The physical connection is either SCSI or Fibre Channel. More than 90% of the connections today are SCSI-based, but the ratio is beginning to swing toward Fibre Channel.

External storage always has been fairly common in the Unix environment, but it is growing in popularity in the PC LAN environment, largely due to server clustering. In many instances, external storage is server independent.

How do you decide whether to go with internal or external storage? In general, internal storage should meet your needs if your capacity requirements are small, you don't intend to cluster your servers, you don't have the space for separate boxes and you are highly committed to one server vendor.

External storage is a good option when you run out of internal storage, want to run server clusters, have a heterogeneous server environment or want to consolidate storage.

Of course, these are just rules of thumb. What's certain is you'll have to give your own decision a lot more thought than you may have in the past.

NWFusion offers more than 40 FREE technology-specific email newsletters in key network technology areas such as NSM, VPNs, Convergence, Security and more. Click here to sign up!		New Event - WANs: Optimizing Your Network Now. Hear from the experts about the innovations that are already starting to shake up the WAN world. Free Network World Technology Tour and Expo in Dallas, San Francisco, Washington DC, and New York. Attend FREE		Your FREE Network World subscription will also include breaking news and information on wireless, storage, infrastructure, carriers and SPs, enterprise applications, videoconferencing, plus product reviews, technology insiders, management surveys and technology updates - GET IT NOW.