Remote tag history provider vs. remote tag provider + local history provider

Ignition
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1

We're preparing to launch a second gateway (for Perspective / IT) that will be connected to our current OT gateway through a gateway network. This OT gateway's default tag provider holds all the tags that drive our shop floor operations and has tag history enabled.

We plan on setting up the OT gateway as the "remote tag provider" for the incoming IT gateway, so we can read all the production tags without affecting normal operations. We want the tag historian to also move to the IT gateway. Regarding the tag historian, it sounds like we can do one of two things:

  1. Set up a local tag history provider on the new IT gateway to historize the remotely-provided tags that are coming from the OT gateway. Or...
  2. Set up a remote tag history provider on the OT gateway to historize the local OT tags using the store and forward system into the IT gateway.

Do I have this right? Is one option recommended over the other -- for example, maybe one is more performant? It seems like option 1 will do better if our main goal is to reduce load in the OT gateway, but this is all new to me so I can't be certain. All guidance is appreciated.

2
  1. Use continuous DB replication from OT to IT outside Ignition, and configure the IT gateway to perform history queries with the replica.

Do not do #1--remote tag providers do not pass tag changes that happen very quickly, and you likely will not get the same historical result.

#2 is OK, but doesn't reduce load as much as #3.

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