fix(mqtt): raise QoS1 retransmit timeout to stop duplicate /status storms#23
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agessaman merged 1 commit intoJul 10, 2026
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…orms esp-mqtt's default message_retransmit_timeout is 1000 ms: any unacked QoS 1 PUBLISH is resent (byte-identical, DUP=1) every second until the PUBACK arrives or the outbox entry expires (30 s). Status messages are the only QoS 1 publishes; on a congested or recovering uplink where broker acks take several seconds, each 5-minute /status was delivered ~6 times, ~1 s apart, as exact copies (same timestamp and stats). Downstream observers flagged excessive_packet_copies and at least one broker treats it as abuse. Expose message_retransmit_timeout via PsychicMqttClient and set it to 15 s in optimizeMqttClientConfig: one retry still fits inside the 30 s outbox expiry, preserving at-least-once delivery while capping duplicates at one. /packets paths are QoS 0 and were never affected.
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esp-mqtt's default message_retransmit_timeout is 1000 ms: any unacked QoS 1 PUBLISH is resent (byte-identical, DUP=1) every second until the PUBACK arrives or the outbox entry expires (30 s). Status messages are the only QoS 1 publishes; on a congested or recovering uplink where broker acks take several seconds, each 5-minute /status was delivered ~6 times, ~1 s apart, as exact copies (same timestamp and stats). Downstream observers flagged excessive_packet_copies and at least one broker treats it as abuse.
Expose message_retransmit_timeout via PsychicMqttClient and set it to 15 s in optimizeMqttClientConfig: one retry still fits inside the 30 s outbox expiry, preserving at-least-once delivery while capping duplicates at one.
/packets paths are QoS 0 and were never affected.