Rockwell Automation FactoryTalk Historian SE 3.0 UniInt Interface User Guide - Manual (Page 59)

UniInt Interface User Manual 53
As a general rule, disconnected startup will not be supported if the Historian SDK is needed
for the interface to start. However, an interface supporting disconnected startup as indicated
in the supported features table which uses the PI SDK by default to retrieve extended point
attribute information from the Historian Server will require additional configuration to take
advantage of the disconnected startup feature. If the host Historian Server is earlier than
version 2, the user must define
/pisdk=0 in the startup command file to disable and prevent
the interface from using the Historian SDK to retrieve extended attribute information from
the Historian Server. If the host Historian Server is 2 or later, the interface will always use
the Historian API to retrieve extended attribute information and not require the
Historian SDK to be disabled.
For Example, the Historian OPC Interface by default is designed to create a PI SDK
connection. If the host Historian Server is earlier than version 2, the interface by default will
use the Historian SDK to retrieve extended point information from the Historian Server. To
use the disconnected startup feature, the user can force the use of the Historian API to
retrieve extended point information from the Historian Server instead of using the
Historian SDK by defining
/pisdk=0 in the startup command file. The extended attribute
field lengths will be limited by the Historian Server version used as shown in the table listed
in the preceding ―Extended Attribute Length‖ section.
Outputs
The interface can be operational in the disconnected startup configuration while the
Historian Server is unavailable. Therefore, outputs will not be supported while disconnected
from the Historian Server. Once the interface establishes a valid connection the Historian
Server, outputs from the Historian Server to the interface will be supported.