你好，我这边碰到一个MQTT问题，就是一个设备在控制台查看已经离线状态，但是通过API查询Session状态还是在线的这不对呀，我截图里的两个状态都是在阿里云上查出来的，一个是控制台，一个是通过管控端API查询的。因为我要限制单点登录，所以每次上线之前我都会去查一下这个设备的Session状态，现...

我的mqtt协议和emqttd开源项目个人理解（4） - 客户端CleanSession=0时，上线接收离线消息，源码分析

学习mqtt协议和emqttd开源项目http://emqtt.com/emqttd源码版本号是v1.1.3。http://emqtt.com/downloads/11131、-module(emqttd_client).[html] view plain copy handle_info({ine...

MQTT获取离线消息小议

作者：俏巴概述微消息队列MQ for IoT在处理离线消息时，为了简化离线消息获取机制，微消息队列系统在客户端成功建立连接并通过权限校验后，会自动加载离线消息并下发到客户端，但是实际在使用过程中会出现消费端启动后迟迟无法获取离线消息的问题，本文主要介绍延迟消息的发送与接收环节需要注意的问题。协...

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更新时间 2024-04-12 10:55:13

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