Gateway restart and tag history


Before I go doing my own testing, I thought I'd ask first.
When a GW is restarted, what happens regarding tags that have history enabled when they're reconnected to their source? Is a historic data point captured, and if so, are deadbands and other capture rules honoured? What if they're memory tags that are only updated by a periodic gateway timer script and the script hasn't run yet? Will these record a data point into history just because the GW restarted?

I also want to know. I have a tag that stores once a day. If I restart the gateway many times a day, will it store multiple times? If the gateway is restarted, and missed the time point of storage, will it make up? (store the tag later? I'm not sure about this word...)

I would think yes and no. Deadbands are an in-memory process that needs to initialize, and I don't think it happens from past history.

As for event scripts and memory tags, that would be entirely up to the script author. A scripted algorithm that uses state would have to initialize that state. The script author can request the latest history for that if desired.

I would think so, yes.

I would think no.

Script your storage if you have particular constraints. (The gateway isn't really intended to be restarted often.)

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