If there is one theme that emerges from successful server consolidation projects, it's specificity. Hand waving like, "just get rid of a hundred servers and we'll save a ton of money," must be replaced by careful inventories of server resources, analysis of communications, software dependencies, data management, storage requirements, and staffing. Since server consolidation most often takes place at the enterprise level, such considerations require much work and expertise.
If you choose to go ahead with consolidation, then planning and implementation are equally demanding. An enterprise obviously doesn't just switch off 300 servers and turn on 100 others, especially if mission-critical software is running on them.
If you can afford it, there are plenty of consulting services available. From IBM, to Sun Microsystems, to an organization down the street, there is no shortage of people with more or less expertise in server consolidation. How effective this support can be depends on what kind of the expertise is available, and whether it stems from common sense or the black arts.
In general, many hardware vendors are happy to perform server consolidation consulting, albeit with a certain bias.
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