Page History

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1. If MQTT Engine is configured to write historical events directly to the Tag, history on the Edge (i.e., Transmission side) must be configured to flush history in order. This means that when the Edge side client comes back online and flushes history, it must flush the oldest historical events first (in order) before sending live Tag changes events to Engine. This is because Ignition will ignore writes to the Tag if the timestamp on the Tag change is older that then current value. Please see the screenshots below for context:

Having the [MQTT Engine Settings -> General -> Miscellaneous -> Store Historical Events] setting unchecked/false…
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Requires the [MQTT Transmission Settings -> Transmitters -> [Your Transmitter… Default/Custom] -> Configuration -> In-Order History] setting to be checked/true
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There are some rules for enabling history on MQTT Engine Tags. They are:

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