Dear Forum,

Topic:PCS7.OPCServer communication problem

Architecture:

PCS7 V7.1 + SP3
Historian Server is Aspentech’s Infoplus.21. A component of Infoplus.21 called CIM-IO is installed on OPENPCS7, which fetches data via PCS7.OPCServer and passes it to Historian server.

Problem Description:
Whenever there is network error or redundancy error within the OSServers themselves, there is a momentary loss of data and sometimes extended loss of data.

• Q1: Error:255,08.02.2013,02:41:21:046,1012200,4,,SVPCSIO04,RedundancyAgent,Outage detected reason 'NetworkError' OR
  
  30/01/13;11:46:41.123;;REDRT:SVPCSIO01:Partner station failed;;ACT;Process control system
• Sometimes this error is very frequent and sometimes not. This error always leads to momentary loss of data. Due to this error, OPCServer loses connection and hence also the Historian. How to fix this error?
• Q2: How does PCS7.OPCServer decides to fetch data from which Server between the master and redundant? In one instance, “SVPCSIO02” was master & “SVPCSIO04” was slave. OPCServer was connected to “SVPCSIO04”. There was network error like above, OPCServer failed to connect to another server ie “SVPCSIO02” and there was permanent loss of data for about 8 hours, by the time we realized it.
• Q3: The clients were all healthy and reported no loss of communication in the diagnostics logs.
• Q4: Does WinCC internally uses separate comm. channel/path for data management to clients and PCS7.OPCServer?
• Q5: How can I look into PCS7.OPCServer to check which Server it is connected to and whether the connection is healthy or not? Also, where are the log files related to PCS7.OPCServer located in the program files? I could not find the relevant path.

Thanks, in advance for all the support and suggestions.
-Ashish