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8th chunk of `content/en/blog/_posts/2016-08-00-Create-Couchbase-Cluster-Using-Kubernetes.md`
20844b026816396f5329e9591422c4daa3d5c939675ea8e3000000010000084a
- TYPE environment variable is set to WORKER. This adds a worker Couchbase node to be added to the cluster.
- COUCHBASE\_MASTER environment variable is passed the value of couchbase-master-service. This uses the service discovery mechanism built into Kubernetes for pods in the worker and the master to communicate.
- AUTO\_REBALANCE environment variable is set to false. This ensures that the node is only added to the cluster but the cluster itself is not rebalanced. Rebalancing is required to re-distribute data across multiple nodes of the cluster. This is the recommended way as multiple nodes can be added first, and then cluster can be manually rebalanced using the Web Console.
Let’s create a worker:



```
kubectl create -f cluster-worker.yml   
replicationcontroller "couchbase-worker-rc" created
 ```







Check the RC:



```
kubectl get rc  
NAME                  DESIRED   CURRENT   AGE  
couchbase-master-rc   1         1         6m  
couchbase-worker-rc   1         1         22s
 ```





A new couchbase-worker-rc is created where the desired and the current number of instances are matching.



Get all pods:

```
kubectl get po  
NAME                        READY     STATUS    RESTARTS   AGE  
couchbase-master-rc-97mu5   1/1       Running   0          6m  
couchbase-worker-rc-4ik02   1/1       Running   0          46s
 ```



An additional pod is now created. Each pod’s name is prefixed with the corresponding RC’s name. For example, a worker pod is prefixed with couchbase-worker-rc.



Couchbase Web Console gets updated to show that a new Couchbase node is added. This is evident by red circle with the number 1 on the Pending Rebalance tab.



 ![](https://lh4.googleusercontent.com/cyrpBtTCFq3rv5YcMvgVdhQN_hQ5WXVxhJSvFdIMQY3GIFJgYVGUpCBrGAp6MBqxHSzfxyEUddF2ijoMncJxKvAgGlKkDMuLOyu0kQKaWi78OW0dmXUtiNQcs0rEEvR_akFtb4UB)



Clicking on the tab shows the IP address of the node that needs to be rebalanced:

 ![](https://lh4.googleusercontent.com/a6-OinZVl2Ij_fnIswNI1TWbbRgkG-KIlfPSaIrGSm36i0GS0Uk0CjcqEW64jGydDE4EpuYC4kaOkSbHi6-3kbwdngRyP-qZMOkM3jpf4dZrhJJ0qHgxUp9GcItUOnR5MzuGQ7kF)
Title: Verifying the Couchbase Worker and Node Addition
Summary
After creating the Couchbase worker replication controller, the worker pod is verified to be running using `kubectl get po`. The Couchbase web console is then examined, showing a pending rebalance notification due to the addition of the new worker node to the cluster. The IP address of the node awaiting rebalance is also visible in the console.