OSIsoft has released a High Availability (HA) PI System, a significant update to the company's enterprise class real-time historian platform. This unified release meets the demands of organizations that depend on the availability of operational data and introduces a boost in protecting data by providing fault-tolerant software that delivers interface failover, buffering, PI Server replication and SDK services.

The PI System is fundamental to the operational strategy of global leaders in manufacturing, energy, utilities and other process industries where access and visibility into mission-critical data is paramount to the success of many initiatives including compliance, energy management and performance improvement.

"Depending on the style of manufacturing, real-time event definition and monitoring may be critical to your composite application. While a failed business transaction can usually be detected and corrected at a later point, long-term damage to assets, brand, and loss of life can result if critical manufacturing events aren't sensed and responded to in a timely manner," said Colin Masson, in the October 2006 AMR Research article 'SOA on Steroids: The Reality of Manufacturing Composite Applications.' "It's no coincidence that data historians have reemerged as a critical foundational element of emerging manufacturing SOAs. This new generation of data historians do much more than aggregate, compress, archive, and trend real-time data. Today they are huge (and sometimes distributed) state detection machines, designed for complex definition and real-time evaluation of complex events."

Even in a simple configuration, there are unavoidable conditions that can trigger data loss or render data inaccessible. While the PI System can prevent data loss during planned maintenance, lack of access to data during a maintenance period may be unacceptable for the end user who depends on timely access to that data. Unplanned downtime represents another potential source of data loss. Cables become exposed, network issues occasionally surface and other situations may arise that can bring down a system momentarily or until such time as a failure is detected and repaired. With the HA release, there is greater assurance that data will always be gathered, stored and available to everyone across the organization. Existing OSIsoft customers can upgrade from PI to PI HA using point-and-click tools that leverage existing operational investments and infrastructure.

Within the release, primary technical advances include: 

• PI Server replication
• Redundant PI Servers including a primary and  one or more secondary servers, together referred to as a "collective."  The PI server configuration tables will be replicated across the  collective.
• Interfaces -- All interfaces will write time-series data directly to  members of the collective, buffering data temporarily for those unable  to receive it for a period of time and assuring that time-series data  stored in each archive is an exact duplicate of the others. 
• Fail-over-Changes to the PI interface design to accommodate HA include  the ability to have a pair of PI interface nodes connected to a PI  Server or to the collective. If the primary interface node fails to  deliver data to the PI Servers, it will fail-over to the secondary PI  interface to run in "hot" standby mode. PI interfaces can now be  started without a connection to the PI server.