Enterprise systems: Fault-tolerant upgrade for real-time historian

By Control Engineering Staff January 11, 2007

Access and visibility into mission critical data are essential for many initiatives, including regulatory compliance, energy management, and performance improvement. Such enterprise-wide data connectivity gets a boost with the release of a High Availability (HA) version of OSIsoft ‘s PI System. This update increases data protection by providing fault tolerant software that delivers interface failover, buffering, PI Server replication, and SDK services.

Thousands of installations worldwide already use the OSIsoft PI System to manage assets, mitigate risks, and identify new market opportunities. 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 certain end users. Unplanned downtime represents another potential source of data loss.

With the HA release, there is greater assurance that data will always be gathered, stored, and available, according to the company. Existing OSIsoft customers can upgrade from PI to PI HA using point-and-click tools. 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 to the secondary PI interface to run in “hot” standby mode. PI interfaces can now be started without a connection to the PI server.

—Control Engineering Daily News Desk
Compiled by Renee Robbins , editorial director