GetSystemName problem in DIST REDUNDANT System
we have problem about DIST REDUNDANT in our architecture.
Our architecture is composed by:
- FIELD SERVER
Redundant system with communication with PLC (S7 plus driver)
System name Sys1 and number name 1
- DESKTOP UI SERVER
Redundant Server "client" system of FIELD server where will be connected client UI.
System name Sys10 and number name 10
We configure DIST and REDU in any config file and this is the final result:
- We have both system in both PARA task (Sys1 and Sys10) but dabase of Sys10 is not online (If dp is modified in PARA of Sys 1 the modification is propagated only in db of Sys1 of DESKTOP SERVER para).
THIS IS CORRECT? IN THIS CONFIGURATION DB IS UNIQUE?
- For the above reason also the object animation (graphic side) works only if Sys1 is included .
THIS IS CORRECT? IS MANDATORY TO INCLUDE SYSTEM NAME FOR ANY ANIMATION?
- The real problem is that all script (for example script ties to topology task) are initialized with GetSystemName function; with this system name the alert summary list result with Sys10 system name instead of Sys1 and ,for this reason, don't work (because Sys10 database is offline)
IS POSSIBLE TO HAVE SYS1 DATABASE REFERENCE OR IS NECESSARY TO CUSTOMIZE GetSystemName FUNCTION?
Thank in advance.
Dist means that systems are sharing db (actually more dpIdentification), not replicating.
For your questions:
- Yes this is normal. If you modify dp in Sys1, then it is in Sys1. Why should it be propagated? Sys10 is already accessing to all dp from Sys1.
- Yes this is also correct. In dist if you need data from Sys1 when having UI running on sys10, then you need to indicate it via prefix Sys1:yourdpname . For anything, script or animation.
- I dont understand why you are using string getSystemName([int systemId]); . If you want to find a point without knowing where it is located, I would suggest to use dpQuery (and alternate dpQueryConnect...) . If you know where point is located, just prefix it. If you call a dp without prefix, then automatically WinCC OA will look only in current connected system (ex if you are connected to Sys10, then it will look here).
I hope it is more clear.
But we have a doubt about this sentence found in the WinCC OA help (for this reason we have a problem about summary alert):
"DPs from other systems (contained in the panels of the topology) are not included in the DP list of the sum alerts of the panels"
Can you help US? How is possible to synchronized sum alert of the two system (sys1 and sys10).
Thanks in advandce.
A summary alert can only contain dp elements for the own system. It is not possible to generate a sum alert which contains dp elements for distributed systems.
Additional information for the answer given by "adaneau": When using a dpQuery() or dpQueryConnect*() function you have to use the REMOTE keyword to specify for which system data shall be queried. If the keyword is not defined the query returns data for the local system.
Using dp element names including the system name in the FROM statement is not allowed.
I have seen that you have also submitted a support service request.
In the future please use only one communication channel for a specific topic.
Senior Support Specialist