RabbitMQ

               RabbitMQ 
               Step 1: Install Erlang/OTP
RabbitMQ requires Erlang to be installed first before it can run. Install Erlang on Ubuntu 18.04 system using our previous guide:
How to install Latest Erlang on Ubuntu 18.04 LTS
Once Erlang has been installed, proceed to step 2.
               Step 2: Add RabbitMQ Repository To Ubuntu 18.04
Import RabbitMQ:
wget -O- https://dl.bintray.com/rabbitmq/Keys/rabbitmq-release-signing-key.asc | sudo apt-key add -
wget -O- https://www.rabbitmq.com/rabbitmq-release-signing-key.asc | sudo apt-key add -
Now add RabbitMQ Repository To Ubuntu 18.04:
echo "deb https://dl.bintray.com/rabbitmq/debian $(lsb_release -sc) main" | sudo tee /etc/apt/sources.list.d/rabbitmq.list
               Step 2: Install RabbitMQ Server Ubuntu 18.04 LTS
To install RabbitMQ Server Ubuntu 18.04, update apt list, then install rabbitmq-server package
sudo apt update
sudo apt -y install rabbitmq-server
After installation, RabbitMQ service is started and enabled to start on boot. To check the status, run:
$ sudo systemctl status  rabbitmq-server.service 
* rabbitmq-server.service - RabbitMQ broker
   Loaded: loaded (/lib/systemd/system/rabbitmq-server.service; enabled; vendor preset: enabled)
   Active: active (running) since Wed 2018-10-24 13:14:42 PDT; 1min 11s ago
 Main PID: 9525 (beam.smp)
   Status: "Initialized"
    Tasks: 87 (limit: 1111)
   CGroup: /system.slice/rabbitmq-server.service
           |-9525 /usr/lib/erlang/erts-10.1/bin/beam.smp -W w -A 64 -MBas ageffcbf -MHas ageffcbf -MBlmbcs 512 -MHlmbcs 512 -MMmcs 30 -P 1048576 -t 50
           |-9622 /usr/lib/erlang/erts-10.1/bin/epmd -daemon
           |-9778 erl_child_setup 32768
           |-9797 inet_gethost 4
           `-9798 inet_gethost 4

Oct 24 13:14:38 ubuntu-01 rabbitmq-server[9525]:   ##  ##
Oct 24 13:14:38 ubuntu-01 rabbitmq-server[9525]:   ##  ##      RabbitMQ 3.7.8. Copyright (C) 2007-2018 Pivotal Software, Inc.
Oct 24 13:14:38 ubuntu-01 rabbitmq-server[9525]:   ##########  Licensed under the MPL.  See http://www.rabbitmq.com/
Oct 24 13:14:38 ubuntu-01 rabbitmq-server[9525]:   ######  ##
Oct 24 13:14:38 ubuntu-01 rabbitmq-server[9525]:   ##########  Logs: /var/log/rabbitmq/rabbit@ubuntu-01.log
Oct 24 13:14:38 ubuntu-01 rabbitmq-server[9525]:                     /var/log/rabbitmq/rabbit@ubuntu-01_upgrade.log
Oct 24 13:14:38 ubuntu-01 rabbitmq-server[9525]:               Starting broker...
Oct 24 13:14:42 ubuntu-01 rabbitmq-server[9525]: systemd unit for activation check: "rabbitmq-server.service"
Oct 24 13:14:42 ubuntu-01 systemd[1]: Started RabbitMQ broker.
Oct 24 13:14:42 ubuntu-01 rabbitmq-server[9525]:  completed with 0 plugins.
You can confirm if the service is configured to start on boot using the command:
$ systemctl is-enabled rabbitmq-server.service 
enabled
If it returns disabled, enable it by running:
sudo systemctl enable rabbitmq-server
               Step 3: Enable the RabbitMQ Management Dashboard (Optional)
You can optionally enable the RabbitMQ Management Web dashboard for easy management.
sudo rabbitmq-plugins enable rabbitmq_management
The Web service should be listening on TCP port 15672
# ss -tunelp | grep 15672
tcp   LISTEN  0       128                    0.0.0.0:15672        0.0.0.0:*      users:(("beam.smp",pid=9525,fd=71)) uid:111 ino:39934 sk:9 <->
If you have an active UFW firewall, open both ports 5672 and 15672
sudo ufw allow proto tcp from any to any port 5672,15672
Access it by opening the URL http://[server IP|Hostname]:15672

By default, the guest user exists and can connect only from localhost. You can login with this user locally with the password “guest”
To be able to login on the network, create an admin user like below:
rabbitmqctl add_user admin StrongPassword
rabbitmqctl set_user_tags admin administrator
Login with this admin username and the password assigned.
               Step 4: Set RabbitMQ Cluster (Optional)
If you need to achieve high availability and higher throughput, consider configuring RabbitMQ cluster on your Ubuntu 18.04 servers by following the guide below:
How to Configure RabbitMQ Cluster on Ubuntu 18.04 LTS
               RabbitMQ User Management Commands
Delete User:
rabbitmqctl delete_user user
Change User Password:
rabbitmqctl change_password user strongpassword
Create new Virtualhost:
rabbitmqctl add_vhost /my_vhost
List available Virtualhosts:
rabbitmqctl list_vhosts
Delete a virtualhost:
rabbitmqctl delete_vhost /myvhost
Grant user permissions for vhost:
rabbitmqctl set_permissions -p /myvhost user ".*" ".*" ".*"
List vhost permissions:
rabbitmqctl list_permissions -p /myvhost
To list user permissions:
rabbitmqctl list_user_permissions user
Delete user permissions:
rabbitmqctl clear_permissions -p /myvhost user