mosquitto

可以将文章内容翻译成中文,广告屏蔽插件可能会导致该功能失效(如失效，请关闭广告屏蔽插件后再试): 问题: What would you suggest for Mosquitto connection pooling in Java? We are wasting (blocking) too much time on establishing each connection, so we think some kind of reuse would be better. 回答1: I'd suggest using the generic object pooling in the Apache commons tools https://commons.apache.org/proper/commons-pool/ But also you could extend Thread to instantiate a MQTT connection object on creation and have a persistent connection per thread. This could be combined with the built in thread pool in the standard class libraries. I assume you do

可以将文章内容翻译成中文,广告屏蔽插件可能会导致该功能失效(如失效，请关闭广告屏蔽插件后再试): 问题: I have a local (OSX 11) mosquitto broker (1.4.7) running with the following config: connection test address test.mosquitto.org topic in_topic in 0 topic out_topic out 0 try_private false notifications false bridge_attempt_unsubscribe true I got the conf settings form here: bridge local mosquitto to cloud broker (thanks) I now have 3 terminals. A : subscribed to test.mosquitto.org directly using a ruby script and ruby-mqtt . B : subscribed to local broker with mosquitto_sub -t in_topic C : publishes using this command: mosquitto_pub -h test

环境：redhat 6 在root前提下，在 /etc/yum.repos.d/下新建mosquitto.repo文件 gedit /etc/yum.repos.d/mosquitto.repo 然后，从官网上找到RHEL6的文件内容： [home_oojah_mqtt] name=mqtt (RedHat_RHEL-6) type=rpm-md baseurl=http://download.opensuse.org/repositories/home:/oojah:/mqtt/RedHat_RHEL-6/ gpgcheck=1 gpgkey=http://download.opensuse.org/repositories/home:/oojah:/mqtt/RedHat_RHEL-6/repodata/repomd.xml.key enabled=1 写入mosquitto.repo中。 之后就可以yum了， yum install mosquitto mosquitto-clients 接着一路选y。 安装完毕。 文章来源: Mosquitto在redhat中的安装

mqtt意为消息队列遥测传输，是IBM开发的一个即时通讯协议。由于其维护一个长连接以轻量级低消耗著称，所以常用于移动端消息推送服务开发。 mqtt协议控制报文的格式包含三部分： 以固定报头、可变报头和有效载荷，其中固定报文头是所有控制报文都有的，可变报头和有效载荷都是部分控制报文。 mqtt是二进制的协议，控制字段是精确到Bit级别的，单纯这一点就足以为其在物联网领域占据一席之地。mqtt是不支持分包等机制，并不适宜一些数据包特别大的应用场景。 使用发布/订阅消息模式，提供一对多消息发布； 对负载内容屏蔽的消息传输； 使用TCP/IP进行网络连接； 具有三种消息发布服务质量选项： 1."至多一次"，通常app的推送使用的是这种模式，也就是说，如果移动设备在消息推送的时候没有联网，那么再次联网就不会收到通知了； 2."至少一次"，可以确保消息收到，但消息可能会重复； 3."只有一次"，确保消息到达一次，比如计费系统，如果出现消息重复或者丢失会导致系统结果不正确的问题。 小型传输，开销很小，协议交换最小化，以降低网络流量； 通知有关各方客户端异常中断的机制。 发布者----发布消息---->代理-------推送消息----->订阅者 发布者----发布消息---->代理<------订阅消息-----订阅者 在mqtt协议中有三种身份： 发布者(publish):发布者是客户端

2，安装客户端paho.mqtt.python import timeHOST="127.0.0.1"//mosquitto 安装的主机ip，127.0.0.1 表示与mosquitto在同一机器上PORT=1883client=mqtt.Client()def on_connect(client,userdata,msg): print("on_connect") passdef on_dis_connect(client,userdata,msg): print("on_dis_connect") passdef mqtt_sub(topic): client.subscribe(topic,1)def mqtt_pub(topic,payload): client.publish(topic,payload,1,1)def mqtt_init(on_message): client.connect(HOST,PORT,60) client.on_connect=on_connect client.on_disconnect=on_dis_connect client.on_message = on_message client.loop_start() def on_message(client,userdata,msg): print(msg.topic+":+"+str

How are users getting past a 1024 connection limit in Linux in association with doing MQTT for push notification? I am using Mosquitto server, which I think I read does not have a 1024 connection limit built into the linux version. So, can I use a single server (no bridging etc) and get 5,000, 10,000+ users? Or, do I absolutely need bridging? I haven't seen a lot of writing on how this is setup other than the config settings man page for mosquitto. Or, can I get by with just modify a few linux configuration settings and I'm good to go with a single mosquitto server? My app is more or less an

I am having two tomcat servers running same web application. Both the web applications subscribe to topic 1 in MQTT server. Whenever message is received in topic 1 both the applications receive the message. But I want only one server to process the request instead of both. The worst case I have to do condition check at both the web applications to allow one time processing. Any suggestions for this case ? You need to use a MQTT broker that supports Shared Subscriptions 1 This feature allows you to have multiple clients subscribed to the same topic and the broker will deliver them in a round

I am trying to run mosquitto_pub on a Ubuntu linux machine as follows: vbhadra@vbhadra-VirtualBox:~$ mosquitto_pub -h iot.eclipse.org -p 8883 --capath /etc/ssl/certs/ -t house/s1 -m "test message" -d Client mosqpub/9204-vbhadra-Vi sending CONNECT Client mosqpub/9204-vbhadra-Vi received CONNACK Client mosqpub/9204-vbhadra-Vi sending PUBLISH (d0, q0, r0, m1, 'house/s1', ... (12 bytes)) Client mosqpub/9204-vbhadra-Vi sending DISCONNECT As can be seen the mosquitto_pub works file. Now I want to experiment downloading the iot.eclipse.org certificate manually and then use that with mosquitto_pub