HOW TO: Install NATS Message Broker

In this post I want to share my approach to installing NATS Message Broker and configure cluster. You can find more information in the NATS documentation http://nats.io/documentation/

STEP 1:  Get NATS

Download NATS using go

1 2	# go get github.com/nats-io/gnatsd # mv /root/go/bin/gnatsd /usr/local/nats/

Create folder for bin

1	# mkdir -p /usr/local/nats/

Create folder for logs

1	# mkdir -p /var/log/nats/

Create folder for config

1	# mkdir -p /etc/nats/

STEP 2:  Create /etc/nats/nats.config for each node

For example if you have 3 node with following addresses:

1.2.1 nats.config srv1

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port: 4222      # port to listen for client connections net: 0.0.0.0    # net interface to listen http_port: 8222 # HTTP monitoring port # Cluster definition cluster {  host: ‘192.168.0.2'  # host/net interface  port: 5222        # port for inbound route connections  # Authorization for route connections  authorization {    user: route_user    password: route_user_password    timeout: 0.5  }  # Routes are actively solicited and connected to from this server.  # Other servers can connect to us if they supply the correct credentials  # in their routes definitions from above.  routes = [    nats-route://route_user:route_user_password@192.168.0.3:5222    nats-route://route_user:route_user_password@192.168.0.4:5222  ] } # logging options debug:   false trace:   false logtime: false log_file: "/var/log/nats/nats.log" # pid file pid_file: "/tmp/gnatsd.pid" # Some system overides # max_connections max_connections: 1024 # maximum protocol control line max_control_line: 512 # maximum payload max_payload: 65536

1.2.2 nats.config srv2

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port: 4222      # port to listen for client connections net: 0.0.0.0    # net interface to listen http_port: 8222 # HTTP monitoring port # Cluster definition cluster {  host: ‘192.168.0.3'  # host/net interface  port: 5222        # port for inbound route connections  # Authorization for route connections  authorization {    user: route_user    password: route_user_password    timeout: 0.5  }  # Routes are actively solicited and connected to from this server.  # Other servers can connect to us if they supply the correct credentials  # in their routes definitions from above.  routes = [    nats-route://route_user:route_user_password@192.168.0.2:5222    nats-route://route_user:route_user_password@192.168.0.4:5222  ] } # logging options debug:   false trace:   false logtime: false log_file: "/var/log/nats/nats.log" # pid file pid_file: "/tmp/gnatsd.pid" # Some system overides # max_connections max_connections: 1024 # maximum protocol control line max_control_line: 512 # maximum payload max_payload: 65536

1.2.3 nats.config srv3

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port: 4222      # port to listen for client connections net: 0.0.0.0    # net interface to listen http_port: 8222 # HTTP monitoring port # Cluster definition cluster {  host: ‘192.168.0.4'  # host/net interface  port: 5222        # port for inbound route connections  # Authorization for route connections  authorization {    user: route_user    password: route_user_password    timeout: 0.5  }  # Routes are actively solicited and connected to from this server.  # Other servers can connect to us if they supply the correct credentials  # in their routes definitions from above.  routes = [    nats-route://route_user:route_user_password@192.168.0.2:5222    nats-route://route_user:route_user_password@192.168.0.3:5222  ] } # logging options debug:   false trace:   false logtime: false log_file: "/var/log/nats/nats.log" # pid file pid_file: "/tmp/gnatsd.pid" # Some system overides # max_connections max_connections: 1024 # maximum protocol control line max_control_line: 512 # maximum payload max_payload: 65536

STEP 3: Create systemd unit “nats.service”:

1	nano /etc/systemd/system/nats.service

nats.service:

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[Unit] Description=NATS After=network.target [Service] Type=simple ExecStart=/usr/local/nats/gnatsd -c /etc/nats/nats.config Restart=always User=root Group=root [Install] WantedBy=multi-user.target

Activate service and start

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# systemctl enable nats.service # systemctl start nats.service # systemctl daemon-reload

 Linux, Message Broker, MQ, NATS