Do the glowing vendor claims surrounding server blades still stand if you cut out the marketing hype? Let's find out.
As an IT Manager, you are likely inundated by positive-spin marketing and vendors touting that their solution is “better, more cost-effective, cheaper, more efficient” and so on. Blade Servers are the latest technology to fall prey to the hype, over-selling and marketing blitzes that follow any new or up and coming technology or product. What happens, though, if we dump the glossy marketing hype and boil-down the facts? Will a distilled overview of what blade servers can really do for you measure up to the claims? Let’s find out.
1. Blade Servers Use Less Power
This bit of hype may be true. In fact, they use up to 28% less wattage than conventional servers. The power in a blade enclosure spreads over the entire enclosure so that the most efficient power configuration is an enclosure full of Blades. The amount of power allocated to each Blade is somewhat vendor-specific and some definitely perform better in this area than others but overall Blades consume significantly less power than their conventional counterparts. Software is also available that can allocate more or less power to specific Blades depending on individual needs.
Mobile processors are also more power efficient than their conventional brethren. These new generation processors use far less power (~50W+) at peak usage times but also have the ability to return to a very low consumption when idle. Newer designs by Intel and AMD have brought some single core processors down to the <10W consumption range.
Conclusion: New design innovations turn hype into hope.
2. Blade Servers Require Less Cooling
In the early days of Blades — say, 5 years ago — this was not true. The hype surrounding the cooling claim is responsible for many IT shops sticking with technology that is more conventional. Early versions of Blades and their enclosures were not airflow friendly but Current Blade and Blade enclosure design is far superior to those of just a few years ago.
Hard drives, CPUs, and Power Supplies are the big heat producers inside a computer. Contemporary Blade Servers come standard with more efficient power supplies that not only consume less power but also give off from 10-25% less heat than earlier versions. Power supplies aren’t the only items to get a contemporary redesign; some vendors are using solid state hard drives with no moving parts that generate almost no heat compared to spinning drives. To decrease heat in Blades further, vendors have not only turned to mobile processors for their power efficiency but also for their reduced heat generation. For those who don’t use solid state technology, some have opted for less power hungry and heat producing 2.5″ drives instead of the standard 3.5″ size.
“The 2.5″ hard drives used in most blade centers usually have a higher failure rate than the typical 3.5″ SAS/SATA drives in non-blade servers,” says Mike Bacher of TulsaConnect Internet Services in Tulsa, Oklahoma. He adds, “[Although] this is changing as time goes on.”
Conclusion: Believe the hype on this one but make intelligent vendor-to-vendor comparisons.
Blade Servers Lower Your TCO
TCO is possibly the most overused three-letter acronym in the technology business. Everything a vendor does for you will lower your TCO but usually after blowing a lot of upfront money on the solution. Blade Servers certainly can lower your TCO by lowering overall power costs for computing power and cooling of the Data Center.
Can Blade Servers provide significant savings in other areas?
They take up less rack space, which means you will pay less money in a hosted environment. Most ISPs who lease rackspace do it on a per rack unit basis. Using Blades will greatly decrease your space consumption in those racks.
Blades are in fact less expensive than the equivalent server with a conventional design is. They have become commodity hardware though their performance compares favorably with standard server architecture. The new generation of Blades is changing the stigma of inexpensive and commodity into a positive attribute. According to some vendor hype, you will actually save money on maintenance and management by deploying Blades. This too may actually be the case due to the ease of racking a new Blade and a minimal provisioning time–a lower cost hardware technician can actually connect the new server and have it available for an OS within minutes of taking it out of the box.
Chris Pritchard, System Administrator at Tilted Planet, Ltd. A Full-service hosting company based in Chicago says that, “We looked at blades but they weren’t cost effective for us because of the special power and cooling requirements. It would have been cost prohibitive for us to rebuild our data center.”
New conventional server deployment requires a lot of planning for power, cooling, network, and space requirements are now practically removed from the equation. Due to the modular nature of Blades, a new Blade connects into the Blade enclosure and immediately has power, network, and a shared management interface.
Conclusion: Blade Servers deliver a lot of bang for the buck and lower your TCO.
Right behind TCO, virtualization is getting a lot of airtime these days. Virtualization uses the resources of one very powerful server to power multiple servers. Each virtual server runs as if it had its own memory, disk space, processor, and other resources. Virtualization and Blades is a Data Center match made in heaven since both technologies are modular in nature. This modularity allows workload spreading or isolation amongst server groups. Today’s virtualization products create pools of virtualized servers to spread the load of consolidated services to multiple Blades.
Companies generally deploy Blades to lower costs but are equally deployed because of the ease of moving multiple underutilized conventional servers onto a single server or cluster of servers. This is the process known as consolidation. Consolidation through virtualization and resource pooling are other ways of maximizing utilization and lowering costs.
Conclusion: Virtualization and Blades are the future of Data Center Computing.
5. Vendor Tie-in/Buy-in
This aspect of Blade technology is not something you are likely to hear as hype so much but as a matter of fact. If you choose to employ Blade technology in your Data Center, you must decide either on a vendor or on some other factors that steer you toward a specific vendor. The reason is that a Blade enclosure from vendor A is not compatible with a Blade from vendor B or any other vendor. If you want IBM Blades, then you have to purchase the IBM Blade solution as a whole. The same goes for Sun, HP, or Dell. Once you buy-in to a specific vendor’s Blade solution, tying you to that vendor exclusively.
Mike Bacher agrees stating, “Once you commit to a blade center, you are locked in to one vendor for additional blades, which could be detrimental from a pricing standpoint.”
Conclusion: Once you buy into a solution, it’s yours to keep.
6. Less Space/High Density
Another truth from the Land O’ Hype? This is the main reason for making the switch to Blade Servers for some companies who use shared floor space. Blade computing, also called High-density Computing, can get you 2-4 times the number of servers into the same rackspace than with conventional hardware. Most Blade enclosures take up about 7U of vertical rackspace but are able to utilize space more efficiently by using an edge-on design. The offerings vary among vendors but you will get from 10-14 servers in a single Blade enclosure. This can represent a significant space savings over deploying 14 standard rack mount servers.
Conclusion: Space is Money.
7. Less Time to Deploy and Provision
As discussed in item 3, Blade Servers take far less time to deploy and provision than convention rack mounted servers because their power, network, remote access, and management are all setup as soon as they connect into the Blade enclosure. As soon as a new Blade connects to the enclosure, it’s ready for an OS and an IP Address. The modular configuration makes setup a quick process that requires less skill and hassle to get a new server from box to rack to live server.
Conclusion: Time is Money.
8. Built-in Redundancy
Although this is somewhat vendor-dependent, built-in redundancy is one of the big selling features of Blade technology. As soon as the server is plugged in, you have redundant power, network, and remote access.
Conclusion: Repeat After Me: Redundancy is Good.
9. Less Cabling
This is another winner and big favorite amongst Blade technology adopters. If you have ever looked at a Blade farm compared to the racks of conventional servers, you may be sold on this one point alone. The days of spaghetti cabling and the nightmarish feeling when you realize the hardware guy didn’t label them correctly (or at all) are gone. Bladed racks are well-groomed and a pleasure to work on. This is where the Data Center gets a makeover.
Conclusion: Hold the Spaghetti.
10. Same Horsepower, Smaller Footprint.
It’s true. The same powerful multi-core, multi-socket servers are now available in Blade format. These days Blade Servers sport the same steroid-enhanced muscle as standalone servers and look better doing it. Originally, this was not the case. Blade Servers suffered having a reputation of being weaker and wiser in the Server Realm and they were. As stated earlier, Blade Servers have undergone significant technological and design makeovers. Today’s Blades are meaner, cleaner, and greener than ever before.
Conclusion: Maximum Power in a Small Package.
Beyond the Hype
Some of the issues concerning Blades that you don’t typically hear from vendors are those relating to local storage, power provisioning, and interoperability (mentioned in item 5). Local storage for Blades is very limited. You can usually use two local drives with a maximum capacity of about 250GB each. If your application requires a high degree of disk I/O, then this can be a limiting factor. For file and print services, some web applications, applications that run comfortably from Network Attached Storage, and network services, converting those services to Blades is relatively easy to accomplish.
When a Blade enclosure is ready for use, all the power needed for a fully populated enclosure generally is allocated all at once. Adding Blades to an existing Data Center may cause you to exceed your practical limits for electrical capacity. It is also possible that your wiring, airflow, and cooling capacity have may need some revision before full deployment.
There is currently no standard format, power requirements, or common interface or enclosure for Blade Servers. You can’t mix Sun, IBM, Dell, or Fujitsu Blades in the same enclosure. Server density per enclosure is also vendor-specific. Some offer 10 Blades per enclosure while others can hold up to 14. These numbers are for standard width Blades; the double-wide ones offer half the density per enclosure.
The hot hype du jour and yester-jour regarding Blades is generally trueâ€”now. It wasn’t a few years ago. Don’t blame the vendors. They weren’t lying to you; they were just prematurely hyping the technology. Blade technology is here to stay and will get even better with time.
Purchasing, provisioning, and using blades requires a large commitment in terms of money, planning, and personnel. It also requires a change in thinking from traditional servers, power, cabinets, and server management. Should you decide to delve into the fascinating and more fact-filled world of Blade technology, remember this one important bit of advice: Determine your needs then cautiously seek out a vendor that can meet those needs.
Kenneth Hess is a Linux evangelist and freelance technical writer on a variety of open source topics including Linux, SQL, databases, and web services. Ken can be reached via his website at http://www.kenhess.com
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