==================
Rancher-setup
==================

Introduction
-------------

One of the larger requirements that this project needs to fulfil is the scalability of the back-end. The migration from monolith to microservice. More about this can be read in the pages referenced in my Scalability page. To allow such a framework change requires a platform in which containers can be run, containing these microservices. The Docker platform is one of those options that can provide this; however, it's use-case is more meant for personal projects. Kubernetes is a more refined Docker, and something I learned is that the maturity of Kubernetes is much higher. It allows for more configuration, which leads me to the opinion that it is more ready for the enterprise production.

Theory
-------

While it is possible to manage your own Kubernetes cluster all from a CLI-interface; for a beginner in this subject it is much more desirable to have a front-end that can translate my input into commands. One of these platforms that delivers this service is Rancher. In this environment, you can set up your own Kubernetes Cluster, but it will be managed by Rancher. Rancher is an open-source tool that has been bought by the SUSE-foundation. 

"Organizations predict that the demand for Kubernetes skills will enjoy a growth rate of more than 67% over the next 10 years."

https://en.wikipedia.org/wiki/Rancher_Labs 

Implementation
---------------

Originally, when starting this project I had good success setting up Rancher; but only found out later that unfortunately I had installed the demo/test version. Then I went back to step one and configured it from scratch using Helm, Kubectl & various few other tools.

Since then, I also upgraded the specifications of the virtual machine that Rancher runs on. 

+----------+-------------------------------+---------------+
| RAM: 8GB | CPU:4 core (3700x AMD Ryzen) | Storage: 60GB |
+----------+-------------------------------+---------------+

As I've been dealing with issues in relation to horizontal pod scalers, this was a required change. 

Then I spun this VM up and ran the following commands one-by-one, as mentioned in the Rancher documentation (that has to be pieced together from various pages, might I add)

.. code-block:: bash

    curl -sfL https://get.k3s.io |  INSTALL_K3S_VERSION=vX.Y.Z sh -s - server
    apt install kubectl
    cp /etc/rancher/k3s/k3s.yaml ~/.kube/config

Then check the deployment using ``kubectl --kubeconfig ~/.kube/config/k3s.yaml get pods --all-namespaces`` 

And then installing Helm by executing this command:

.. code-block:: bash
    
    helm install rancher rancher-stable/rancher \
    --namespace cattle-system \
    --set hostname=rancher.my.org \
    --set replicas=3

After adding the ``rancher.my.org`` to my host file I could access the dashboard through my browser.

.. image:: https://i.imgur.com/WsYluFN.png