Negative implications of unplanned downtime are certainly chief concerns for every business. But often overlooked is the fact that no two downtime incidents are the same. One data center's momentary inconvenience could be another's demise.
For this reason, it is crucial to classify the criticality of each facility, which requires an understanding that the vulnerability of an organization is directly attributed to the weakest link in its chain. A wide range of relevant factors including HVAC and electrical systems, facility security, IT infrastructure maintenance and operations and disaster preparedness must be incorporated to ensure the reliability of the facility and its data center.
Assessing the availability and reliability of a business's critical facility using the aptly named Criticality Levels concept is useful for existing facilities and during the design process. This helps to select the proper components that complement the critical mission of the facility and safeguard its data center against downtime.
Below is an example of how these criticality levels can be determined:
- The loss of availability for a C2 facility could widely affect productivity. Full recovery after momentary unplanned downtime can potentially take hours. Maintenance downtime can be regularly scheduled.
- C3– Back-up corporate facilities supporting and/or including critical business processes. The loss of availability widely affects productivity and directly affects customers. Full recovery after momentarily unplanned downtime can take hours or even days. Maintenance during low-risk windows can be scheduled monthly or quarterly.
- C4– Primary corporate facilities that support and/or include critical business processes. The loss of availability widely affects productivity and directly affects customers. Full recovery after momentarily unplanned downtime can take hours or even days. Online maintenance with moderate risk windows can be scheduled monthly or quarterly with blackout periods, and maintenance shutdown is extremely difficult to schedule.
- C5– Primary corporate facilities supporting and/or including core business processes. The loss of availability directly translates to the facility's bottom line. Full recovery after momentary unplanned downtime can take days to possibly weeks. Online maintenance with low-risk windows can be scheduled quarterly or annually with blackout periods. Maintenance shutdown cannot be scheduled.
- C6– Large corporate data centers supporting and/or including core business processes and are, typically, a network of remote data centers that work together. The loss of availability poses widespread circumstances that can affect national security and public safety. Full recovery after momentary downtime can take weeks to months and all maintenance must be performed online and must be extremely low-risk.
- C7 and beyond– Future levels for continued growth and evolution of the critical facility.
Enabling facility planners and IT directors to assess the importance and level of quality needed for various external components, such as standby power, security, IT configuration and IT redundancy is the primary purpose for these definitions. For example, a C6 facility such as a large corporate data center must have significantly more IT redundancy than a C1 facility that is simply supporting office processes.
When facility designers understand the level of criticality, combined with an assessment of all of the external components supporting its operations, they are enabled to provide the needed flexibility, redundancy and security to support the organization's critical mission.
About the authors:
Jerry Burkhardt is the P.E. and vice president of commissioning services at Syska Hennessy Group. He has over 21 years of specialized experience in critical and live environments.
Richard Dennis is the P.E. and vice president of national commissioning services for Syska Hennessy Group. He has over 30 years of professional engineering experience in design management, construction, and facility operations.
This was first published in October 2006