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Summary: It is not difficult to build an MQTT server on linux CentOS. It mainly uses mosquitto, a message broker service software. It adopts publish / subscribe mode transmission mechanism, which is lightweight, simple, open and easy to implement. It is widely used in the Internet of things. MQTT is a client server based message publish / ...

1. Apache pulsar installation and deployment 1.1 preliminary preparation zookeeper 3.4.5pulsar installation package 2.8.1Cluster security free environment 1.2 deployment steps 1.2.1 upload the installation package to the linux server Download address: https://pulsar.apache.org/zh-CN/download/ 1.2.2. Unzip the file to the data directory ...

The rocketmq version is 4.9.2. The version of rocketmq spring boot starter is 2.2.1 1, Code Producer code App class package com.zgd.springboot.demo.simple; import java.util.Date; import com.zgd.springboot.demo.simple.mq.MQProducer; import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.Sprin ...

1, Message queue 1.1 related concepts of MQ 1.1.1 what is MQ MQ(message queue), in its literal sense, is essentially a queue. FIFO is first in, first out, but the contents stored in the queue are messages. It is also a cross process communication mechanism for upstream and downstream message delivery. In the Internet architecture, MQ is ...

Source Version 4.8.0 demo code for the official Consumer consumption message DefaultMQPushConsumer consumer = new DefaultMQPushConsumer("please_rename_unique_group_name_4"); // 1. Set NamesrvAddr address consumer.setNamesrvAddr("127.0.0.1:9876"); // 2. Set Consumer Location Optional Value Reference Enumeration Co ...

The article is long. It is recommended to collect it before reading it In the previous article, we introduced the NameServer startup process and several core points involved in NameServer startup: Load the NameServer configuration class and NettyServer configuration class, and create the core component NamesrcControllerInitialize various data ...

1. Semaphore There are two kinds of semaphores: counting semaphores and binary semaphores. Counting semaphores can be obtained multiple times. Binary semaphores have only two states: 0 and 1, and can only be obtained once. Semaphores can be used to protect resources and prevent multiple tasks from accessing a resource at the same time. Create ...

Producer principle Producer overview         The party sending the message is called the producer. His role in the entire RocketMQ production and consumption system is shown in the figure:         Producer group: a logical concept. When using producer instances, you need to specify a group name. A ...

Use Java to simulate how consumers consume messages in rabbitMQ message queue introduce General summary: the producer produces a message and stores it in the message queue in rabbitmq, and then the consumer takes the message out of the message queue. In this part of this tutorial, we will write two programs in Java. The producer who send ...

I read a lot on the Internet and copied the official website README. I didn't explain many important things clearly. I had to study it myself.My blog, keyword Less-Bug.com, welcome to pay attention.Introduction to NSQnsqd: daemon, client communication. Default port 4150 (TCP) 4151 (HTTP)Nsqlookupd: equivalent to a router. The client can discove ...