Blade servers are sometimes referred to as a poor man's supercomputer. Some people like to make them sound very complex, but they are actually very elegant, simple devices.
At its most essential, a blade server is a chassis that snugly holds swappable blades, so it's similar to a bookshelf or a CD rack. Each blade is an independent server. A blade will have its own processor, hard drive, operating system and so on. Once the blade is plugged into the chassis, it gets to share power, optical drives, ports and switches with all the other blades. More importantly, it gets to share resources.
The cost of blade servers vary, but I have seen 64-bit blade systems starting out for as little as $1,500. In some cases, you can achieve the same power and number of servers with white box servers for a little less money up front. Beyond the initial cost, a blade server helps IT managers save some dough by using less data center floor space. Cabling is simpler, too, which cuts down on labor costs. Reduced cable clutter also saves space. Blades have only one power cord and one Ethernet cord per chassis.
With blade servers, you receive huge amounts of processing power in a small package at a reasonable price. You are also gaining some peace of mind. Consider these options:
- Most blades are hot-swappable. If you're experiencing a traffic surge, you can move some blades from one department over to your Web server, temporarily, with no downtime.
- No downtime when blades break. Should a blade break, as all hardware does eventually, you can just pull the blade out and plug in a new one when the replacement part arrives.
- Blades offer redundancy options. In the same chassis, you can have one set of blades be your live server with another set serving as your back up system.
What about practical applications for blades? If you are in the market for a simple file server, blades might be overkill. If you have a huge problem that would require a large server farm, you may want to consider a mainframe solution to avoid the dreaded HVAC (heating, ventilation and air conditioning) issues that could result from the high-power density inherent in the blade server design. However, if you are looking for a powerful Web hosting or clustering solution that is economical and makes use of limited space, then a 64-bit blade cluster is exactly what the doctor ordered.
Considering all of these factors, you might be thinking that blade servers are an attractive solution. Why would you want to run them on Linux?
From my own experience, I can say that Linux is a good option for organizations that want to save money and increase IT stability, security and power. However, before taking a step into the unknown -- if Linux is an unknown to you -- you'll need some facts to support your decision. So, think about the well-substantiated facts about Linux associated with three important areas:
- Cost. It is possible to legally install and configure all the software you need for a Linux platform without spending any money. If you want built-in commercial-grade support and features, there are well-tested, commercial distributions (which are packaged operating systems like Red Hat Enterprise Linux and SUSE Enterprise Server) available. In general, commercial, enterprise-level Linux distributions' subscription fees are less costly than proprietary operating systems' license fees. In fact, some proprietary operating systems cost more upfront than the hardware does.
- Security. Linux is not 100% immune to viruses. Some have been created in proof-of-concept labs. Face it, there are thousands of viruses every year for Windows, but none for Linux. That does not mean there won't be some one day, but Linux Land is a much safer neighborhood to live in. In addition, Linux security flaws are fixed swiftly by distributors and the open source community. Most of the time, a fix is produced within hours. With proprietary operating systems, fixes takes longer, even as long as a few months.
- Stability/Power. Linux has always been a true multi-user, multi-tasking platform. Linux distro makers also understand something their proprietary platform peers don't: one size does not fit all. When necessary, tools are removed or added to make specific servers more efficient. Because Linux source code is open, it's a lot easier for IT managers to tweak distributions to optimize them for servers. Distribution vendors and users can compile Linux kernels to match the hardware, resulting in highly-optimized, extremely fast systems.
To sum it up, a Linux-based, 64-bit blade server offers power, space savings, security and -- in most cases -- cost savings over other server and operating system platforms.
Editor's note: Coming next is this series are tips on preparing for a migration, how to perform the migration and what problems or concerns to expect with resources to get past them.
About the author: Patrick Green is president of Silver Strand Solutions, an IT consulting firm in Bolinbrook, Ill., that specializes in Linux and open source software implementations.
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This was first published in September 2006