They're called blades for two reasons. First, these systems-on-a-card are thin, compared to what complete systems normally look like. If you step back far enough, they look like blades. Second, they are the computer industry's latest example of that time-tested revenue-producing strategy known as "razors and blades."
Printer manufacturers are notorious for this practice. Inkjet printers (the razors) help HP and other printer makers generate substantial income from ink cartridges (the blades). In the world of servers, you will first be asked to buy special enclosures (the razors), and then you will need to fill them up with servers (the blades). HP is already boasting of how its customers are buying "10-packs" of blades, as if they were an impulse buy at the check-out counter.
2003 will be the first full calendar year that real blade offerings are available from the top three Intel-based server providers: Dell, HP, and IBM. The game is on. (The lesser known RLX Technologies has been working hard to get a leg up in this niche before the big boys take it over.) Off the big three, HP has been the only blade game in town for close to a year now. If you've been buying HP's enclosure, then you're already stuck buying their blades. It also means you probably don't have to read any further. Nothing I write here is likely to make you switch-- especially since HP's systems, like IBM's, have a proprietary relationship with the company's server management software.
But if you're like the majority of your contemporaries --- barely spending any money and taking note rather than stock of the blade market -- read on. As it turns out, the aforementioned management software is probably one of two things that will ultimately sway your decision should you decide to pursue a blade server strategy. The other is price.
I can hear the product managers from IBM and HP cursing me now. How dare I trivialise the work that went into streamlining the industrial design of their boxes? (Dell has yet to start its rollout.) But for the most part, those designs are focused on stuffing as much into each blade as possible, maximising blade density (the number of blades per enclosure), minimising the number of cables popping out of the back of those enclosures, optimising the sharing of resources like power supplies and network switches, integrating storage area network technology, and other cool features like the hot-swapping of everything from the blades themselves to fans to memory and hard drives.
The devil is in the details, and there are already some subtle differences from one vendor to the next. But the moment that one vendor releases details of its latest offering, the other vendors will rush those details to their engineers, who will go back to their drawing boards to catch up. Regardless of provider, however, the results of these engineering stunts are invariably some fairly stunning achievements for those of us who cut our teeth on refrigerator-sized servers--easy-to-provision, fault-tolerant servers and pretty blinking lights in a relatively tiny place that has remarkably few cables coming out the back.
One key hardware difference worth noting is the choice of processor in the dual processor blades. HP is using 1.4 GHz Pentium IIIs with a 133 MHz system bus that was especially built by Intel for dual processing in high-density blade scenarios. IBM appears to have done its own engineering to bring Intel's 2.4 GHz Xeon DP processors (with a 400 MHz system bus) for the dual processor blades that will go into its recently announced BladeCenter. Like HP, Dell appears to be going with Pentium IIIs.
Both IBM and HP have waved their competitive pricing flag at me, but it's hard to factor this into my assessment since the pricing I see and what corporations really pay varies wildly. Besides, the fact that IBM, HP, and Sun are routinely slitting each others throats with new price cuts to sell servers (and Dell routinely walks in as the low-cost value provider that no one can touch), most companies have their own private discount schedules that don't map very closely to the prices I'm given for publication.
Your decision may very well come down to the software side. Aside from space and power savings, the big advantage of blade servers is the flexibility offered to IT managers who like to quickly allocate or re-allocate server resources. In situations where a network manager must provide server resources to keep up with demand spikes, the right management tools can help to quickly provision a server with an operating system/applications/data image, bring up that server, and incorporate it into a VLAN as an additional resource that a good load balancing solution can take advantage of. Blades are ideal for these situations. On top of that, you still need all of the other typical server management tools that can handle tasks like asset management, predictive component failure, and forwarding of management data to enterprise management systems like HP's OpenView and IBM Tivoli's Enterprise Console.
We're still awaiting details on how Dell's OpenManage portfolio of management software is going to cover the range of management and provisioning activities. Both HP and IBM have released their specifications and both companies offer a very rich set of management solutions. HP's solution has taken the scripting capabilities of Compaq's InSight Manager and married it to solutions from partners like Altiris (for provisioning and software distribution) and F5 Networks for load balancing. IBM's management solutions, including IBM Director and Tivoli software, are homegrown.
Your choice of blade strategies may very well hinge on the management software with which you're most comfortable. Perhaps that's a choice you made a long time ago, well before blades were the rage. None of the management solutions are as good at managing the other vendors' hardware as they are at their own. That's because all of the management solutions take advantage of custom silicon found in their related systems. If you already have a solution in place and are using it, my advice is to stick with that vendor's hardware solutions--unless there's something you absolutely need and only one vendor has it at the time you have to make a choice (like Xeon DP processors).
If you're new to the game, ask the blade warriors to spend a day showing you what their management software is capable of and what the charges for that software are. While there are some differences at the hardware level, the various vendors will close some gaps and open up others. No hardware or price advantage lasts for very long (unless it's Dell). But you'll need good software to take full advantage of all that cool hardware. So, rely on the software as the showcase for what the hardware can do and then write to me to let me know what you decided.
