Summary: MQTT: PINGRESP was sent too late
Project: lwIP - A Lightweight TCP/IP stack
Submitted by: giusloq
Submitted on: Tue 11 Jun 2019 07:40:15 AM UTC
Priority: 5 - Normal
Assigned to: None
Discussion Lock: Any
Planned Release: None
The first PINGRESP (keep-alive) was sent only after 2 *
MQTT_CYCLIC_TIMER_INTERVAL. If MQTT_CYCLIC_TIMER_INTERVAL = 5s and keep-alive
is set to 5s too, the first PINGRESP is sent 10s after the connection.
In this case, the server (MQTT Broker) could force a disconnection if the
PINGRESP message isn't received in 7-8s after connection.