Network visibility in the data center

Current trends toward Virtualization, Converged Enhanced Ethernet (CEE), Fibre Channel over Ethernet (FCoE), Service Oriented Architectures (SOA) and Cloud Computing are part of a broader re-architecture of the data center in which enterprise applications are decomposed into simpler elements that can be deployed, moved, replicated and connected using high-speed switched Ethernet.

The following example, shown in the diagram, illustrates the management challenges faced in this new environment. A system manager decides to move a virtual machine from one server to another. The system management tools show that there is plenty of capacity on the destination server and this looks like a safe move. Unfortunately, the move causes the storage traffic, which had previously been confined to a single switch, to congest links across the data center causing system wide performance problems.

In this new environment the traditional siloed approach in which different teams manage the network, storage and servers does not work. An integrated approach to management is needed if the full benefits of a converged data center are to be achieved. Ensuring network-wide visibility into the storage, network and services running in the data center, their traffic volumes and dependencies is a critical component of an integrated management strategy.

In order to achieve data center wide visibility, every layer of the data center network, including the core, distribution, top of rack and blade server switches, needs to be instrumented. This might seem like a daunting (and expensive!) challenge. However, most vendors have integrated sFlow into their switch products. The sFlow standard provides a proven solution that is available in network products from the leading computer and network vendors, including HP, IBM, Dell, Brocade, BLADE, Juniper, Force10 and 3Com (for a complete list, see sFlow.org). Making sFlow a requirement when building out a new data center is a sound investment, adding very little to the cost of the network, but ensuring that the visibility needed safely deploy, optimize and scale up new services is available to the operations team.