Do not read one of the regret series to understand the use of LinuxCentOS to build MQTT server and client operation

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 / ...

Posted by olidenia on Sun, 05 Dec 2021 20:12:05 -0800

[notes] Apache pulsar learning manual

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 ...

Posted by steveswt on Wed, 01 Dec 2021 02:49:29 -0800

Try RocketMQ, transaction messages, and not_ CONSUME_ The yet message cannot be consumed

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 ...

Posted by Paul_Bunyan on Fri, 26 Nov 2021 16:47:25 -0800

Message middleware RabbitMQ

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 ...

Posted by GreenUser on Fri, 26 Nov 2021 01:21:21 -0800

Days of Pull Source Analysis of RocketMQ Consumer Startup Process and Messages (Nursery Level Analysis)

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 ...

Posted by Jbert2 on Thu, 25 Nov 2021 10:58:06 -0800

RocketMQ source code analysis - Broker startup process and registration principle

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 ...

Posted by mdgottlieb on Mon, 22 Nov 2021 12:39:55 -0800

Some understanding of semaphores, mutexes, mailboxes and message queues in RTOS

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 ...

Posted by thefarhan on Sun, 21 Nov 2021 16:43:45 -0800

Rocket MQ Series II - producer principle

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 ...

Posted by jayskates on Tue, 16 Nov 2021 07:31:23 -0800

Use Java to simulate how consumers consume messages in rabbitMQ message queue

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 ...

Posted by ashii on Tue, 09 Nov 2021 15:11:05 -0800

Golang NSQ message queue usage practice

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 ...

Posted by mabans on Mon, 08 Nov 2021 23:18:21 -0800