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Delay in new tags being replicated to Secondary Data Archive

Question asked by RolandRich on Mar 30, 2016
Latest reply on Apr 1, 2016 by bshang

I have an older PISDK application that creates PI tags and writes values to them. The PI Data Archive is an HA Collective of 2 servers (Primary and Secondary both running PI 2015). The application uses the (latest version) of the PI buffering subsystem to fan and buffer data to both members of the collective.


However, if the application creates a new tag, and immediately attempts to write a value to this tag, the value does not reach the Secondary Data Archive. Looking at the PI message logs, you can see that it takes about 9-10 seconds after being created on the Primary for the new tag to be replicated and created on the secondary. During this time, the secondary will not accept values for the tag.


One simple way I have worked around the issue is to just wait for 20 seconds after creating the tag, before I write values to it. This gives the PI collective enough time to replicate the new tag to the secondary (and presumably register the new tag with the buffering subsystem on the client).


However, this workaround is not particularly neat. I was wondering if anybody else had encountered this issue before, and if so, what workarounds they have for it.