RabbitMQ Cluster in Kubernetes

(Using the rabbitmq-clusterer plugin)

This is an example of how one might implement a rabbitmq cluster in Kubernetes using the clusterer plugin. Advice, input and pull requests on how to improve this would be greatly appreciated.

References:

• https://github.com/rabbitmq/rabbitmq-clusterer
• https://www.rabbitmq.com/clustering.html
• http://thesoftjaguar.com/posts/2014/06/18/rabbitmq-cluster/
• https://hub.docker.com/_/rabbitmq/
• https://docs.docker.com/registry/
• https://stedolan.github.io/jq/

Prerequisites

This readme assumes you are familiar with running Docker plus Kubernetes/Minikube. You also need to run a Docker Registry.

Build the docker image

docker build -t localhost:5000/com/example/rabbitmq_clusterer . 

Push the image

docker push localhost:5000/com/example/rabbitmq_clusterer

Start rabbitmq services

kubectl create -f kube/rabbitmq-clustered-service1.yaml
kubectl create -f kube/rabbitmq-clustered-service2.yaml
kubectl create -f kube/rabbitmq-clustered-service3.yaml

Start replication controllers

kubectl create -f kube/rabbitmq-clustered-rc1.yaml
kubectl create -f kube/rabbitmq-clustered-rc2.yaml
kubectl create -f kube/rabbitmq-clustered-rc3.yaml

Apply the cluster configuration on one of the containers

# login to a pod
# your pod name will vary
kubectl exec -it rabbit1-gwoxt bash 
apply-cluster-config.sh

Check if the cluster configuration succeeded

kubectl logs -f rabbit1-gwoxt

If successful you'll see the following at the end of the log stream:

 =INFO REPORT==== 19-Dec-2016::02:36:19 ===
 rabbit on node rabbit@rabbit2 up
 
 =INFO REPORT==== 19-Dec-2016::02:36:19 ===
 rabbit on node rabbit@rabbit3 up

Start the rabbitmq round-robin service

     kubectl create -f kube/rabbitmq-clustered-svc.yaml

Describe the rabbitmq service:

 kubectl describe service rabbitmq-svc
 Name:			rabbitmq-svc
 Namespace:		default
 Labels:			name=rabbitmq-svc
 Selector:		type=rabbitmq
 Type:			NodePort
 IP:			10.0.0.172
 Port:			amqp-tls	5671/TCP
 NodePort:		amqp-tls	30399/TCP
 Endpoints:		172.17.0.5:5671,172.17.0.6:5671,172.17.0.7:5671
 Port:			amqp	5672/TCP
 NodePort:		amqp	31200/TCP
 Endpoints:		172.17.0.5:5672,172.17.0.6:5672,172.17.0.7:5672
 Port:			mgmt	15672/TCP
 NodePort:		mgmt	30849/TCP
 Endpoints:		172.17.0.5:15672,172.17.0.6:15672,172.17.0.7:15672
 Session Affinity:	None
 No events.

Load the rabbitmq management console in your browser

The exposed port for the management console in this example is: 30849. See NodePort: mgmt 30849/TCP above

http://<docker-host>:30849

View cluster overview

# Full overview
curl -s http://guest:guest@<docker-host>:30849/api/overview|jq .

# See which node you are connecting to
curl -s http://guest:guest@<docker-host>:30849/api/overview|jq .node

Management console example