Chapter 2
Server Consolidation via Clustering
Server consolidation via clustering offers a true benefit of reducing the total number of managed
systems on the network. In addition, consolidating to a shared data cluster provides greater
flexibility with backups, the ability to load balance client requests, and failover support.
Although shared nothing cluster architectures offer failover support, they do not provide true
load balancing. This can only be achieved by consolidating to a shared data cluster.
Shared data clusters offer the benefit of scaling to meet both changes in client load and storage.
Because they run on industry standard hardware, scaling is an inexpensive option. Furthermore,
consolidating to shared data clusters offers significant savings in cost of ownership and software
licensing. Consolidating a large number of servers to a shared data cluster results in the need to
maintain fewer OS, backup, and antivirus licenses. With fewer managed systems on the network,
administrators will have fewer hardware and software resources to maintain on a daily basis.
With substantial cost savings over proprietary NAS appliance solutions, shared data clustering
has emerged as an easy fit in many organizations.
Planning for Growth While Maintaining Freedom
When planning for growth while consolidating, there are several best practices to keep in mind.
When planning to consolidate the network, consider the following guidelines:
" Design for scalability
" Design for availability
" Use mature products
" Avoid proprietary hardware solutions
One of the most over-used words in the IT vocabulary is scalability. However, it is often one of
the most important. Scalability means that all elements of the network infrastructure restructure
should support company growth, both expected and unexpected. For example, if current
requirements warrant the purchase of an 8-port fibre channel switch, consider purchasing a 16-
port switch. Ensure that the planned SAN switches offer expansion ports so that the option is
available to scale out further in the event that growth surpasses projections.
Scalability can also be greatly aided by the use of centralized management software. Many of the
solutions previously mentioned in this chapter can help with centrally managing storage
resources and backups across the enterprise. If performance is an issue, another major scalability
concern should be in technologies that support load balancing of client access. Such technologies
alleviate single server bottlenecks that result from unexpected client growth.
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