Wednesday, February 8, 2012
The data center paradox
In today’s globalized environment organizations are spread geographically across the globe. Such globalizations result in multiple advantages ranging from quicker penetration into foreign markets, cost advantage of the local workforce etc. This globalization results in the organization having data centers that are spread in different geographical areas. Besides mergers and acquisitions of different businesses spread across the globe results in hardware and server sprawl.
Applications in these dispersed servers tend to be silo’ed with legacy hardware and different OS’es and disparate software that execute on them.
The costs of maintaining different data centers can be a prickly problem. There are different costs in managing a data center. The chief among them are operational costs, real estate costs, power and cooling costs etc. The problem of hardware and server sprawl is a real problem and the enterprise must look to ways to solve this problem.
There are two techniques to manage hardware and server sprawl.
The first method is to use virtualization technologies so that the hardware and server sprawl can be reduced. Virtualization techniques abstract the raw hardware through the use of special software called the hypervisor. Any guest OS namely Windows, Linux or Solaris can execute over the hypervisor. The key benefit that virtualization brings to the enterprise is that it abstracts the hardware, storage and the network and creates a shared pool of compute, storage and network for the different applications to utilize. Hence the server sprawl can be mitigated to some extent through the use of Virtualization Software such as VmWare, XenApp, Hyper-V etc.
The second method requires rationalization and server consolidation. This essentially requires taking a hard look at the hardware infrastructure, the application and their computing needs and trying to come up with a solution which involves more powerful mainframes or servers which can replace the existing less powerful infrastructure. Consolidation has multiple benefits. Many distributed data centers can be replaced with a single consolidated data center with today’s powerful multi-core, multi-processor servers. This results in highly reduced operational costs, easier management, savings from reduction in the need for power and cooling requirements and real estate saving etc. Consolidation truly appears to be the “silver bullet” for server sprawl.
However this brings us to what I call “the data center paradox”. While a consolidated data center can do away with operational expenses of multiple data centers, result in reduction in power and cooling costs and save in real estate costs it introduces WAN latencies. When geographically dispersed data centers across the globe are replaced with a consolidated data center, in a single location, the access times from different geographical areas can result in poor response times and latencies. Besides there is also an inherent cost of data access over the WAN network
The WAN network results in latencies which are difficult to eliminate. There are technologies which can lessen the bandwidth problem to some extent. WAN optimizer is one such technology.
In fact e-commerce and many web applications intentionally spread their application across geographical regions to provide a better response time.
So while on the one hand consolidation results in cost savings, better efficiencies of management of a single data center, reduced power and cooling costs and real estate savings it results in WAN latencies and associated bandwidth costs.
Unless there is a breakthrough innovation in WAN technologies this will be a paradox that architects and CIOs will have to contend with.