The Pros and Cons of Server Consolidation
One of the hottest prospects to address the high administrative, support and infrastructure costs of the data center is server consolidation. "In the long term, server consolidation is something you absolutely must do," says Tim Pacileo, executive consultant at Compass American Inc., a metrics-based IT consulting firm based in New York City.
However, along with consolidation's significant advantages, there are also significant challenges that may diminish its benefits. "The cost savings look great on paper," concedes Pacileo. "But once you consider all the factors, you understand that you might not realize all those savings right away."
Together At Last
Server consolidation involves gathering data and applications stored or running on two or more physical servers onto a single server. This reduces the number of physical machines required to meet all the processing and/or storage requirements of the data center. Some organizations take this concept a step further through virtualization, which makes a single physical server look like multiple logical servers. Either way, there are a number of ways in which consolidation reduces the data center's total cost of ownership (TCO):
- Lessened hardware requirements Because it's no longer necessary to purchase a new server for every application or business unit, you can cut the total number of machines. When each department has its own dedicated servers, these reductions can be dramatic.
- Minimized physical space Fewer servers mean less total space dedicated to your data center.
- Reduced energy costs Likewise, fewer physical servers in a reduced physical space means reduced energy required to heat and cool the facilities. As energy costs continue to escalate, cutting down on servers can result in significant (article continues)
savings. "With the current drive toward 'green' data centers, this is a major business driver," says John Sloan, a senior research analyst at Info-Tech Research Group, in London, Ont., Canada.
- Decreased labor and support costs Experts estimate that more than 70 percent of the TCO of the data center derives from administrative, labor and outsourced services. Server consolidation should slash those expenses. "Just take the amount of time it takes to provision a new server," says Jacob Farmer, chief technology officer at Cambridge Computer Corp., a consulting firm specializing in data protection and storage networking, located in Waltham, Mass. "Before, you had to order it, transport it to and from the loading dock, screw it into the racks and configure it. Today, all you need to do is sit down at a terminal and conjure up a new virtual server."
Curb Your Enthusiasm
Before moving ahead with consolidation plans, though, data center managers must consider a number of challenges. Chief among them: disaster recovery. "You have to have a backup machine that has the same capabilities of each production server," Pacileo points out. "These hardware costs -- and the related support costs -- can add up, and reduce your anticipated savings."
An added detriment: In the past, when a server went down, it might inconvenience a couple of hundred people. Now, says Pacileo, "If you consolidate 30 servers onto one, and that goes down, you take down thousands of users. The risks are much greater."
Paradoxically, because it's so easy to create new virtual servers on existing hardware, many data centers find the number of logical servers proliferating, leading to higher complexity and greater related support costs.
"It's so easy to get as many virtual servers as you want without jumping through hoops," says Farmer. "People think, 'Why not just create another server?' without thinking through the ramifications." (article continues)
Follow a Plan
Implementing an effective server consolidation is a four-step process, according to Chris Taylor, director of professional services at Evolving Solutions, a Minneapolis, Minn.-based consulting integrator specializing in server and storage virtualization:
- Assess "The first step is taking an inventory of each existing server, and the applications or data that reside on them," says Taylor. "You have to understand the dependencies and utilization of all the resources that applications take today so you can anticipate your future needs."
- Design Data center managers must design the way the data center will look after the consolidation by specifying which servers will be consolidated together.
- Migrate IT organizations should begin the transfer of data slowly, with lower-priority applications, and take a phased approach to consolidation.
- Optimize Finally, data center managers must continue optimizing the server consolidation effort through continuous monitoring of performance and capacity. It's critical to establish a baseline to measure the existing state of server utilization, related hardware infrastructure, and support costs for comparison with post-consolidation metrics. One caveat: "In some cases, data centers end up with more virtual than physical resources, and they are back to where they started in terms of complexity and support costs," says Taylor.
Despite today's challenges, businesses looking to cut costs, increase utilization, and promote organizational effectiveness will inevitably choose consolidation. "As we move from decentralized, department-centric ways to manage computing resources back to a centralized model, reducing the number of servers is the required first step," Sloan says.