Go green by monitoring storage environmentals

By John Webster and Chris Stakutis

John Webster
Chris Stakutis
Data center operations are undergoing a "sea change" driven by virtualization, converged storage and server networks, and the emergence of environmental sustainability as a key consideration for IT. All of these drivers are interrelated. Server and storage virtualization coupled with network convergence can lead directly to more efficient use of energy in the data center. In this article, however, we focus on the impact of something that is far simpler and easier to do: metering and monitoring your storage-related energy usage and heat load – your storage environmentals.

Most data center operations managers would agree that if you want to cut the electricity bill substantially, attack the server environment first. But suppose you've already done that. You've virtualized and consolidated, and now feel comfortable that you've done what you can for now to run a "greener" server environment. What comes next? Consider storage.

Many articles have been written about how storage virtualization and technologies such as data deduplication and thin provisioning save energy. But do you know how much money you actually save by running a thinly provisioned array, for example? Or how much energy deduplication actually saves? Can you accurately measure the energy impact of these storage-related services?

Take a look at your storage environment today. Through high-density disk drives, thin provisioning and data deduplication (and other data reduction technologies), you can now store hundreds of terabytes in a single rack. But what impact does compacted storage have on data center heat load? A single rack of storage could now represent all of your corporate data because you've been consolidating and virtualizing, and that's good. But do you know what load that rack represents to your UPS systems and backup generators? Could a single alarm in your HVAC system ruin your week?

If you could monitor power consumption more granularly, and in real time, you could:

  • Better understand your exposure to outages related to power and HVAC in real time
  • Measure the energy-related impact of further storage consolidation
  • Predict the energy-related impact of additional storage capacity

Data center virtualization and consolidation projects have at least one unintended consequence: "liability per square foot" skyrockets. It is now time to use new tools to get deeper insight into the details of your storage-related energy consumption, as well as visibility into the impact storage has on the underlying facility systems that ultimately support all IT operations. With that data in hand, you could mitigate exposure to energy- and heat-related outages, reduce costs, and perhaps even appease the folks around the table at the next Sustainability Committee meeting.

The good news is that real-time measurement and monitoring of storage environmentals is relatively inexpensive and can be done now. It requires the implementation of sensory data collecting devices, and the integration of these devices with a software application that allows you to both visualize and manage the impact your storage has on IT facilities.


The required instrumentation is non-invasive and available today. Wireless network-based sensors that can be strategically placed in critical points within the data center, attached to equipment racks, and even clipped around power cords can measure:

  • Current electricity levels flowing through power cords and other electrical sources
  • Temperature
  • Liquid flow and leak detection
  • Air pressure
  • Air particulate density

These devices can be installed in minutes, and most of them have a heritage in the network monitoring world so you can be assured that they are ready for the big leagues.

Metering, monitoring, visualizing

Next comes the addition of a software tool that takes the data collected from the wireless sensors and presents it to the data center administrator. These applications are available from a number of sources, including sensory device vendors as well as many of the IT management applications vendors you may already be using to manage other aspects of your IT environment. You should look for features that are already common to these types of management applications, including:

  • Device discovery and mapping
  • Alert notifications and alarms
  • Notification of "near threshold" conditions
  • Statistical analysis and reporting tools


Armed with the data coming from sensors that are monitoring the storage environmentals, you can now take better control over your storage-related power consumption and heat load requirements, ultimately reducing your potential exposure to outages related to data center environmental factors. By gathering and charting measurements over time, you can predict the impact of adding another drive rack to an array, for example, or increasing storage utilization from 25% to 50% within an array. You can more accurately predict energy cost savings that could result from implementing deduplication. Additionally, you may be able to include, or more accurately account for, energy and HVAC costs when charging back user groups for storage services.

Being a storage administrator now means you have to worry about a new set of problems related to extreme density and compounded by high energy costs and a corporate mandate to be more "green." However, it's easier than you think to take control over your storage environmentals.


JOHN WEBSTER is a principal IT advisor at the Illuminata research and consulting firm, and CHRIS STAKUTIS is vice president of emerging technologies at CA.

This article was originally published on September 01, 2009