MQTT data loss for QoS 0 messages

Incident Report for Clarify

Resolved

We have had an MQTT processing issue with data loss between 03:19 AM and 09:24 AM CEST, affecting MQTT messages sent with QoS 0 (Quality of Service "at most once"). This includes all MQTT messages sent via the Sparkplug B standard. We have identified and addressed the underlying issue, so data now flows normally.

Data that have been sent via MQTT using QoS 1 ("at least once") will potentially arrive at a delay. Message sent directly via the Clarify input API are not affected.
Posted Jun 10, 2026 - 03:00 CEST