Pros: Depending on the age of a legacy system, expensive support and maintenance contracts can be eliminated.Since the number of administrators and support labour is usually correlated to the number of individual servers, having fewer servers generates proportional administration and support labour savings.Costs to implement physical consolidation are low, and consist of network enhancements to support the centralization, datacentre build-out to support the consolidation, and physically moving the servers. Cons: The risks are performance degradations due to poor network planning and business resilience risks by having all of the server assets in "one basket," particularly if the datacentre does not have adequate recovery plans.
This process can be difficult and can introduce management burden and complexity.
Many business units will not support logical consolidation where they must share servers, and will need to be "sold" on the business merits of consolidation and assured that service levels will hold steady or increase.
Cons: Establishing workload optimization configuration and rules will take some time and can be complex, requiring professional services assistance.
As with logical consolidation, business unit apprehensions and business resilience best practices apply.
Because the analysis is complex, internal IT teams should consult with independent analysts and performance benchmarking sites (such as org and put vendors to task (with requisite scrutiny), to help propose and analyze current opportunities and various consolidation options.
Comparing the solutions' TCO and service levels head-to-head with a TCO analysis tool can provide the team with visibility into potential savings, and provide justification needed to empower the business to make the right decision.
Using logical consolidation, hard partitions can be established for the operating system, application, processors and memory requirements so that these individual server "islands" are pooled onto a single server or cluster.
That way, fewer servers are needed because headroom is reduced and the applications are hosted on a single cluster.
Tom Pisello is the founder and CEO of Orlando, Fla.-based Alinean, an ROI consultancy and software provider. For more information and exclusive access to server TCO analysis tools and white papers, visit
There has been a strong trend toward more server consolidation since 1997, led by enterprises in the United States, Canada and Western Europe.
It can also eliminate the cost of moves, add-ons, and changes (MACs), as well as break-fix maintenance and support by eliminating travel time and expenses.