Getting started with Karbon

If you look at Nutanix' solution brief for Nutanix Karbon it says "Who knew Kubernetes could be so simple?" and yes it is that simple!

I don't know much about containers and I still struggle to see many uses for them. Regardless of what I think, my manager is keen to explore its abilities and provide support if our developers want to use them. I had to start from scratch and do a lot of reading. To get familiar with all the jargon I started playing around with Docker and Kubernetes on my MAC. Very easy to install and you will be creating containers in no time. Having access to an enterprise Azure subscription I started looking at their offerings. Azure Container Services is no longer available and has been replaced by Azure Kubernetes Services. I did manage to get AKS to work but not without involvement from Microsoft Support. Too complicated and time consuming for me. I also feel that financially AKS may not be the cheapest option.

How about setting up a Kubernetes cluster on prem? Yes, tried that too. I deployed 3 Centos VM and installed Kubernetes on top of it. There are some great references on how to do this but again I found it complicated and time consuming, took me a few days. Although it all seems to work as expected, this is definitely not a setup I would take into production.

Being a big Nutanix customer it made sense to look into Nutanix Karbon and as with all things Nutanix it is supposed to be simple to install. When I first looked at Karbon it was still a technical preview and although I could see immediately that it would be a whole lot simpler to get up and running I did run into some issues. My deployments did fail and I had to get support involved. The things that were highlighted by support were:

• Upgrade to latest PRISM
• Upgrade AOS
• Disable proxy settings
• Limitation in networking port groups returned.

In the mean time Karbon had gone GA so before dealing with the above I updated Karbon via LCM. Worked flawlessly. I am a big fan of LCM and if you attended .NEXT you may have seen me on stage during the LCM session.

Upgrading PRISM and AOS was a breeze as per usual. The proxy settings need to be disabled for Karbon to work. This is a known issue and hopefully will be solved before too long. I have a requirement for a proxy in my environment and when I disable it I cannot upgrade my components.
We also encountered an issue where I could not select correct network for node VM. This was due to the fact that I have many network ports in my ESX environment and the Karbon UI did not like that.  We worked around this issue by prefixing network name with AA

Let's have a look at the install of Karbon...

• Log into PRISM and go to Services > Karbon
• Enable Karbon
  
  

• Once Karbon has been enabled you will be asked to log in to Karbon console
• Upload an image by selecting URL and enter http://download.nutanix.com/karbon/0.8/acs-centos7.qcow

• Click upload file and change image name to acs-centos and click save

• Click create cluster and select Development cluster
  
  
  
  
  
  
• Enter name for K8s cluster and specify Nutanix cluster
  
  
  
  
  
  
  
• Specify network. I have also changed the worker resources to 2 from the default 1 instance
  
  
  
  
  
  
• Accept the defaults for networking
  
  
  
  
  
  
• Enter your credentials and accept the other defaults. Click create
  
  
  
  
  
  
• Once your cluster is deployed you should see a green heart your cluster has been deployed successfully.
  
  

• Select the cluster and from actions menu, download kubeconfig
  
  

• You can set your KUBECONFIG variable to the downloaded file or merge the context into your existing config file (.kube/config) if you need to connect to multiple clusters.

At this stage you should be ready to start deploying containers and this is where you will need some Kubernetes knowledge. Let's verify a few things to see if everything is in order....

• From your CLI, type kubectl config get-contexts. This will show you which clusters you'll have access to. One is the Karbon cluster and the other is my docker-for-desktop setup on my Macbook, which is defult context at this stage.
  
  
  
  
  
  
• Switch to the Karbon context with command "kubectl config use-context KarbonPilot4-context"
  
• Run kubectl cluster-info and you'll get the address where Kubernetes Master is running
  
  
  

We are pretty much ready to deploy a container on our Nutanix platform. The best way to deploy containers is by having all your code in a yaml file but that is outside of scope for this post.

• Run "kubectl create deployment nginx --image=nginx" to create deployment
• Verify with "kubectl get deployments"
• Get more info on Nginx deployment "kubectl describe deployment nginx"
• Make the container accessible "kubectl create service nodeport nginx --tcp=80:80"
• Check if your service was created with "kubectl get svc"
  
  
  
  
  
• Open a browser window. Pick the public IP of any of the master/slaves nodes followed by the port above. 
• Your container is available
  

I am hoping to go into a bit more detail about some of the other features that Karbon uses in a future post