kubernetesdemo: A repository from techievee

Kubernetes configurations

The repository contains various strategy for implementing the Kubernetes cluster from Source code.

Approach 1 (servian-auto.yaml) - ( Deployment time is ~5 minutes )
- In this approach, the Docker image is build using the Docker hub automated githooks.
- Git hook is configured in the Dockerhub with the Github source repository.
- As soon as a commit is performed on the repository, the build trigger, triggers the build.
- The images are build using a "auto" tag, so this image is pulled when using the servian-auto.yaml file.
- Dockersecrets are not required in the configuration as there is no push of image
```
   git clone https://github.com/techievee/kubernetesdemo.git
   kubectl apply -f servian-auto.yaml
```
Approach 2 (servian-build.yaml) - Deployment time is ~30 minute ( more time is taken for angular build)
- In this approach, the Docker image is build and pushed to the repository during the deployment.
- This approach is more appropriate in a environment, where we have our own registry for container repo. kaniko( docker in docker) image is used for building the container image.
  - In this approach, whenever the container is initialized
  - Kaniko container pulls the source code from the repository
  - Builds the image for the container
  - Pushes the build images to the docker registry using the configured docker credentials
  - All the images build using this method are tagged as "kaniko"
- The image with the "kaniko" tag is pulled when using the servian-build.yaml file.
- Dockersecrets are required in this configuration as build image is pushed to registry

This process can also be done using CI/CD Tools automatically

            git clone https://github.com/techievee/kubernetesdemo.git
            kubectl apply -f servian-build.yaml

Accessing Web interface of deployed Application

One all the pods are deployed, then type, to see the result

http://minikube_ip_address:30111

Where IP of minikube can be got by running the command * minikube ip DNS name of the minikube can also be used instead of the IP address

Test bed configuration

The kubernetes configuration were tested using the minikube for Windows
The minikube was configured to use Hyper-V of windows 10, and started using the command
4GB memory allocation for the minikube VM.
minikube should be given a access to Network adapter with external access

Accessing the minikube using the internal dns name which is autocreated(minikube) from the host.

    minikube -p servian start --vm-driver hyperv --hyperv-virtual-switch "External Switch" --cpus 4 --memory 4096

"External switch" is the name of the switch, please refer the name in your Hyper-V network settings.

Important

DNS from your host system should be getting resolved using minikube
Try nslookup minikube

Ports Exposed as Nodeport

Golang exposes the API in port : 30112
Angular exposes the web interface : 30111

Kubernetes dashboard enabling

The dashboard of the minikube can be enabled by running

 kubectl apply -f https://raw.githubusercontent.com/kubernetes/dashboard/v2.0.0-beta4/aio/deploy/recommended.yaml
 minikube -p servian dashboard --url

Kubernetes components and its usages for various purpose:

Redis - Deployed using Stateful set
Redis Disk - Deployed using the Persistent volume and Persistent Volume Claim
Configuration for Golang - Using the ConfigMap
Password for Redis, Docker hub - Using Secrets
Angular Application - Using the Deployment
Golang application - Using the Deployment
Access to Golang and Angular - Using the Nodeport service (30111- Angular, 30112- Golang)
Access to Redis - No External access, Access via kube-dns( redis name) via clusterip service
Building and Pushing container - Using Kaniko image (Running docker in docker) as Onint container or as Jobs

References

The project uses other 2 project

https://github.com/techievee/godemo
https://github.com/techievee/angulardemo