Applies To:
  • CitectSCADA 5.xx, 6.00
  • CitectHMI 5.xx, 6.00
Summary:
I have two alarm severs located in different time zones. I have found that duplicate alarm summary events are showing on my alarm summary pages. I have also looked through the alarm save file in a text editor and can see that the records do seem to match.

I noticed that this occurs after I restart my secondary alarm server but I am using a reverse pair of primary and standby alarm save files as outlined in the Help. Can this be resolved?

 

Solution:
The alarm events use universal time (UTC) so there is no problem having alarm server pairs in different time zones. In a redundant system, where both primary and secondary alarm save files are being used, and one alarm server has been offline for a period, on secondary alarm server startup the alarm events are updated from the most recent alarm save file. If there are a large number of events and delays, then the update may not complete successfully. The [Alarm]StartTimeout parameter value can be increased from the default 120 seconds up to a maximum of 3600 seconds. This should resolve the problem.

Presently, if the time is not sufficient, the error message "Timeout from RndAlarm Server" is written to the Citect Kernel Main window. This may be addressed in a future release by also providing a hardware alarm and syslog.dat entry. Further, duplicate entries can then be added in the secondary alarm save file and seen in the alarm summary events by the secondary alarm save file updating from and to itself. Citect has confirmed this to be a problem in CitectHMI/SCADA versions up to and including CitectHMI/SCADA version 6.00. We are researching this problem and will post new information here as it becomes available.

Importantly, in CitectHMI/SCADA version 6.00, which provides a configurable increased alarm summary events size, the functionality and the [Alarm]StartTimeout parameter has been changed to the time allowed for updating each packet from the primary alarm server rather than all items. Therefore occurrence of this problem is believed unlikely. Citect has confirmed this omission from the current CitectHMI/SCADA version 6.00 Help.

 
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