(2) RabbitMQ actual combat – rabbitmq high availability cluster construction

Preface

This section is about the deployment and construction of a rabbitmq high-availability cluster. The centos7 system is used. We prepare three servers as rabbitmq's high-availability servers. The rabbitmq cluster itself does not naturally support high availability. We configure the mirror queue of the rabbitmq server. To ensure that messages can be replicated and stored on multiple nodes in the cluster, improve availability and fault tolerance, and avoid single node failure.

rabbitmq high availability cluster server planning

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①Upload rabbitmq installation package to server hadoop101, hadoop102, hadoop103

②The server uses the rpm command to install the erlang environment respectively

Command:

sudo rpm -ivh erlang-26.2.3-1.el7.x86_64.rpm

Check whether erlang is installed successfully:

③Use rpm command to install rabbitmq server

Command:

sudo rpm -ivh rabbitmq-server-3.13.0-1.el8.noarch.rpm

④Start rabbitmq server

Command:

#Set rabbitmq server to start automatically at boot
systemctl enable rabbitmq-server
#Start rabbitmq server
systemctl start rabbitmq-server
#View rabbitmq server status
systemctl status rabbitmq-server
#Stop rabbitmq server
systemctl stop rabbitmq-server
#Restart rabbitmq server
systemctl restart rabbitmq-server

⑤Open rabbitmq’s web client rabbitmq_management

-Open the web client of rabbitmq server

rabbitmq-plugins enable rabbitmq_management

-Use a browser to access the rabbitmq client

- Add the account accessed by rabbitmq

# Create user
rabbitmqctl add_user <username> <password>
# Set user role
rabbitmqctl set_user_tags <user> <Role>
# Set user permissions
rabbitmqctl set_permissions [-p <vhostpath>] <user> <conf> <write> <read>
# View users
rabbitmqctl list_users

- Use the created rabbitmq account admin to log in to the web terminal

⑥Configure the mapping between host name and host address to facilitate servers to access each other through host names. For information about secret-free access between servers and mutual transfer of server files, please refer to the author’s previous blog content

⑦ Synchronously distribute the cookies of hadoop101 server rabbitmq to hadoop102 and hadoop103 to ensure that each node uses the same cookie

scp /var/lib/rabbitmq/.erlang.cookie root@hadoop102:/var/lib/rabbitmq/.erlang.cookie
scp /var/lib/rabbitmq/.erlang.cookie root@hadoop103:/var/lib/rabbitmq/.erlang.cookie

⑧Execute the following commands on the hadoop102 and hadoop103 nodes respectively to join the nodes to the cluster

- Start the rabbitmq service in the background

rabbitmq-server -detached

- Shut down rabbitmq server

rabbitmqctl stop_app

- reset rabbitmq server

rabbitmqctl reset

-rabbitmq joins the cluster

rabbitmqctl join_cluster rabbit@hadoop101

- Start application

rabbitmqctl start_app

- View cluster status

rabbitmqctl cluster_status

⑨ The rabbitmq node exits the cluster, taking the hadoop103 node exit as an example

- Stop hadoop103 node application

rabbitmqctl -n rabbit@hadoop103 stop_app

- Remove hadoop103 from any node of hadoop101 or hadoop102

rabbitmqctl forget_cluster_node rabbit@hadoop103

- View cluster

⑩Create a mirror queue to achieve synchronization between rabbitmq message clusters

- Under normal circumstances, the rabbitmq cluster is not highly available, and data between nodes cannot be shared. It is necessary to use a mirror queue to synchronize node data and introduce a mirror queue (Mirror Queue) mechanism. If a node in the cluster fails , the queue can automatically switch to another node in the mirror to ensure service availability

- The mirroring strategy has been added. Multiple strategies can be added according to specific actual needs.

- Check whether the policy is in effect

- Stop node 101, the cluster can still be used normally, failover occurs, and other nodes take effect

- Restart node 101 and restore the number of replicas

Conclusion

At this point, the tutorial on building a rabbitmq high-availability cluster ends here. See you in the next issue. . . . . .