Rabbitmq use and reliable sources

Install a .rabbitmq

Description: erlang and rabbitmq versions need to match, you can view the official website matching relationship

1. Install erlang environment

yum install erlang

erlang -version to see if the installation was successful

2. Install rabbitmq

yum install rabbitmq-server

4. Set the boot from the start

chkconfig rabbitmq-server on

5. Set Profile

cd /etc/rabbitmq

cp /usr/share/doc/rabbitmq-server-3.4.1/rabbitmq.config.example /etc/rabbitmq/

mv rabbitmq.config.example rabbitmq.config

Configurations to the configuration example and rename rabbitmq

6. open the configuration file remote access

we /etc/rabbitmq/rabbitmq.config

The open configuration {loopback_users, []}, remove the end comma

7. Turn on the web interface management tool

rabbitmq-plugins enable rabbitmq_management

8. firewall port 15672 open

Or turn off the firewall

Permanently open port: firewall-cmd --permanent --add-port = 15672 / tcp

Reload open ports: firewall-cmd --reload

Check the status of: firewall-cmd --state

View open ports: firewall-cmd --list-ports

centos7 used systemctl firewall management

# Systemctl start firewalld # start,

# Systemctl enable firewalld # boot

# Systemctl stop firewalld # close

# Systemctl disable firewalld # cancel boot

9. commonly used commands

//start up

service rabbitmq-server start

// Check status

service rabbitmq-server status

//shut down

service rabbitmq-server stop

II. Create a user

1. Log Management page

http://101ycy.com:15672/ guest guest

2.admin tab add admin users, roles for the administrator

3. Role Type

Super Administrator: administrator, can log management console to view all the information on the user, the policy (policy) operate

Monitoring by: monitoring, management console can log in to see mq node information (number of processes, memory usage, disk usage, etc.)

Policy makers: policymaker, you can log management console for policy management, but can not view mq node information

General manager: management, can only login management console, can not see the node information, the policy can not be managed

Other: Can not log management console, often it is the producers and consumers

III. Create a virtual host

1. Definition: the equivalent of a library database

2. meaning: a virtual host holds a group of switches, queues and bindings, the user can do right controls the particle size of the virtual host in the rabbitmq

IV. Work six models introduced

1. Simple Queue

Switch is not specified, sent directly to the queue

2. Work Queue

Basic with simple queue, multiple queues consumer spending, the default polling distribution, you can set basicQos (perfetch = 1), consumer manual answer ack, will send a message, the process can ensure faster we receive more news

3. routing mode (switch to direct the direction switch)

Switches and to bind the queue, and sets routing keys routing key

Message to the carrying direction switch routing keys and will be delivered to the queue corresponding

4. publish subscribe model / broadcast mode (switch to switch fanout sector)

And a plurality of switch queues Binding

The switch will send a message to deliver to all queues bound

The wildcard / theme (topic switch to switch)

Similar routing mode, but the routing keys can contain wildcards

# Routing key matches one or more words, * matches a word, e.g. hello.word, hello. *, Hello. #

Five .rabbitmq usage scenarios

1. asynchronous processing

Such as user registration, send text messages and e-mail alert; anti-fraud system calls Data Services Platform is an asynchronous call

Advantages: call without waiting for the end result

2. Application of Decoupling

The system data from the A to the B-system, with a strong dependence MQ queue can be lifted, if failure does not affect the B-system A and Messaging

3. Traffic clipping

Preventing influx of a large number of system request messages First mq, and then at a rate of consumption mq message

4. Message Distribution

The message buffer

VI. Concept Note

1.broker: Message Queuing service entity

2.exchange: message switches, the message specified rule, the relationship between the process and the message queue, the queue can be bound may be bound switch

3.queue: queue, the message into the queue

4.binding: bind, bind by the switches and queue routing rules

5.routing key: routing keys, switches the message delivery according to this

6.vhost: virtual news servers, completely isolated vhost, switches, and can not be shared between different queues vhost, is mainly used to divide different business modules, access control can be done

7.producer: producer, posted a message

8.consumer: consumer acceptance message

9.channel: channel, in order to open the channel of communication, a channel assignment on behalf of a session, is a virtual connection on a real tcp

Use VII. Died switch

Consumers through basic.reject refused or undeliverable will be placed in the queue here for troubleshooting news

VIII. Send message acknowledgment

confirm (confirm callback) return (failure callback) / callbak

1. queues and to switch: performing ack = true

2. Switch error, correct queue: the implementation of ack = false

3. Switch right, I was wrong queue: a failure to perform execution ack = true

4. switches and queues are wrong: performing ack = false

IX. Reliable Message Delivery

Two programs: the following figure, the picture from the network

The message persistence, performance almost

Message delivery delay, do the second check, the RPC fails to re-send the message, but the message delay delivery of messages can fail, just more than a layer of protection

In addition some of the ways to add:

One is the use of transaction mechanism rabbitmq producers set to open affairs, and notes on sending transactional method, the rollback exception occurs, each submission will block waiting for service processing returns result, large performance impact is generally not used

1. configuration

Persistence configuration: switches, queues and persistent messages are set to

Normal switch configuration: the theme or routing mode

Backup switch configuration: broadcast mode (this configuration without routing Key), and binding two queues, queues and alarm undeliverable message queue, alert queue is used to send e-mail, text messages timely alarm

Binding backup switch: normal switch configuration alternate-exchange parameter specifies the name of the backup switch can bind

Trigger conditions: when the message queue is not properly delivered to the switch of the normal, will send messages to the backup exchange

Backup switch also receive: At this point triggers confirmcallback and returncallback, you need to enable

Confirmcallback not reach the switch trigger is false, can not reach the queue trigger returncallback

Process:

When posting switch, the write msg id and redis, if the write fails mongodb delivery switch according to the msg id read redis confirm the recording as a message delivery failure, then the timing task scan redelivery, the sign of successful successful

If forwarded to the queue fails, the message is written mongo, ibid.

2. Description simple and reliable delivery: normal delivery switch, if it fails to deliver the backup switch, or if it fails to confirm the return messages to the callback in Mongo, redelivery scan and update the status timer

3. Reliable consumption

Consumer actuates the manual answer mode, the processing is successful basicAck, two parameters, a unique identifier, all other disposable ack message less than all of the unique identification

And fails basicReject requeue = false, the process proceeds to the switch if the dead letter badmail switch, two parameters, a unique identifier, whether the second re-placed in the queue

Badmail switch configuration and dead letter queue:

The producer can be configured

Illustrated as follows: from https://blog.csdn.net/Weixiaohuai/article/details/94760975