The secret is out about the benefits of virtualization and server consolidation at headquarters and in the data center, in terms of capital savings as well as reductions in power and cooling expenses and maintenance costs. Branch office operations are often left out of that conversation, which is understandable but unfortunate.
It's understandable, given that national and multinational corporations have many geographically dispersed branch offices, making the technology installed in those locations more of a sprawling management challenges. But it's unfortunate, since consolidation of branch office environments represents a major opportunity for savings from server virtualization. Done right, branch office technology consolidation can both save money and improve the level of service provided to branch office workers.
According to a study by Forrester Research, branch offices average about 10 servers each. The study also found most companies reported that between one-third to half of company data also resides in these branch offices, often because of locally deployed email servers and other IT services that largely duplicate functionality that exists elsewhere. In other research, Forrester has found that most organizations use more energy in their branch offices than they do at headquarters. So if you confine your energy-saving efforts to your centralized operations, you may be missing the bigger opportunity for savings. That goes for the potential savings in hardware and maintenance costs as well.
According to VMware, you can expect every server virtualized to save 7000kWh of electricity annually, or about $700 in energy costs. Virtualizing a server also saves about 4 tons of CO2, the equivalent to taking 1.5 cars off the highway.
We do see that organizations that have already gotten serious about the consolidation of centralized technology operations are starting to look outward to their branch facilities. Charged with achieving continuing cost reductions, enterprises are looking for any opportunity to cut fat rather than muscle and bone.
However, consolidation of branch server resources does pose different challenges, just because the branch office is by definition remote from centralized information technology resources. Typically, virtualizing branch office servers entails moving them to a central data center and providing branch employees with remote access to their services.
Of course, it's also possible to deploy a virtualization host to a branch location, so that multiple servers can be consolidated onto a single box. That would achieve some hardware and power savings, but not the simplified administration and maintenance you would get from pulling the whole package back to the data center. If you are going to do this, you might as well do it right. In other words, you want to push for your branch offices to be 'serverless,' or close to it anyway. And you want to accomplish it without compromising application performance for branch office users.
One thing you must get right in your quest for a serverless branch to pull this off is to invest appropriately in your wide area network (WAN), and consider WAN optimization to compensate for the distance between branch offices and the data center. If your branch offices are going to be dependent on central services for critical functions, such as access to customer data, that WAN link had better be efficient, reliable and blazingly fast. This is not just a matter of how much bandwidth you purchase from your friendly telecommunications provider. You also need to look at issues like latency-the delay in transmission introduced by distance, even for signals traveling at nearly the speed of light. While you can't change the laws of physics, you can use WAN optimization appliances to cut down on the amount of network chatter that must pass back and forth to accomplish a given task, such as downloading a file or posting a ledger entry. These tactics can give you LAN-like performance over a more economical WAN network architecture.
Often, branch server consolidation is pursued side-by-side with other initiatives that also place more demand on the wide-area network, such as Voice over Internet Protocol telephony (VoIP) and collaborative software that incorporates voice and video. In the Forrester study, almost 50 percent of organizations reported using IP voice and videoconferencing to help drive down travel costs. This is another reason WAN optimization is essential, because without it voice and video transmissions are often jittery. Employees and executives will only take maximum advantage of these services if they're high quality-almost as good as being there.
I've discussed some of the WAN issues for server consolidation, but there is one piece I left out. Even with WAN optimization, there are some servers used to provide basic network services that don't make sense to centralize. For example, the domain controller that provides IP addresses to PCs in the branch office ought to be located in the branch office. The same goes for the print server that queues up jobs to be fed to printers within the branch. Making a print job bounce from a PC in the branch to a server in the data center, and then back to the printer down the hall would be the reductio ad absurdum of server consolidation.
So does that mean we have to give up on the goal of a serverless branch office? Not necessarily. One way to address the need for a limited number of local services is to host them on the WAN appliance itself. By definition, an appliance is a simplified computing device requiring less management than a standard server. But a relatively recent option added to some of these appliances is the ability to act as a host for a limited number of virtual machines. Typically, those VMs would be used for the handful of services that clearly benefit from local deployment. For example, some organizations might want to use them to provide firewall and other security services, in addition to print servers and other core network 'edge' services that benefit from being as close to the user as possible. A well-designed WAN optimization appliance can provide fine-grained control of data flow through these virtualized services, just as if they were on independent servers.
With that addition, some organizations will find it's possible to clear out the entire server room at a branch location and replace it with a WAN optimization appliance alone. Even if carrying consolidation to that degree is not practical, dramatic reductions in the number of servers maintained in a branch are clearly achievable.
Server consolidation in the data center is already a hit in many organizations. But the sequel may be even better. If yours is an organization with a sprawling branch network, the time to start consolidating it is now.