Rockwell Automation FactoryTalk Historian SE 3.0 UniInt Interface User Guide - Manual (Page 67)

UniInt Interface User Manual 61
Creation
CAUTION: The interface will create a point cache file and digital set cache file
necessary for the disconnected startup configuration. These files are automatically
generated by the interface and are locked while the interface is running. To
prevent data loss, these files must not be modified by the user when the interface
is not running.
The creation mode ensures the interface has the necessary cache files needed for the
disconnected startup configuration. The two files necessary for this configuration are the
point cache file and digital set cache file. If one or both of these files is missing, the missing
file or files will be created. The files by default are created in the same location as the
interface executable. If the path to the executable cannot be established, the Historian API
will provide a default location based on information available to the application. In all cases,
the filename and location are logged in the pipc.log file. The ―Messages‖ section of this
document contains a listing of typical messages sent to the pipc.log file during the creation
mode. The file name is constructed using the executable name, host name, point source, and
id provided by the startup command file. The point cache file will have the form
filepath/exename_hostname_pointsource_id_ptcache.dat
Likewise, the digital cache file will have the form
filepath/exename_hostname_pointsource_id_dgcache.dat
For example, if the file path to the executable is ― C:\Program Files\Rockwell
Software\FactoryTalk Historian\PIPC\Interfaces\Test ‖, with an executable
name of ― Test ‖, host name of ― FreeBird ‖, point source of ― abc ‖, and an id of ― 1 ‖, the
point cache and digital cache files created in the directory indicated by the path to the
executable would have the following name:
c:/program files/pipc/interfaces/test/test_freebird_abc_1_ptcache.dat
c:/program files/pipc/interfaces/test/test_freebird_abc_1_dgcache.dat
Part of the creation process includes storing Interface and Historian Server versioning
information in the each of the files to be used in the validation process. Therefore, a
connection to the Historian Server must be available during the initial creation process for
the disconnected startup operation to be configured.
Note: If either of the caching files fails to be created, an error message will be logged to
the pipc.log file and the interface will fail to start.