Knowledge Base for IT Professionals, Teachers and Astronauts
Docker images are stored on the host to launch as fast as possible. The drawback is, Docker can fill the hard drive with unused images. A recent possible bug in Docker caused the accumulation of unused, unreferenced images on the host. To delete all Docker containers and images, use these commands in the terminal Get …
Continue reading “How to remove all Docker containers and images from the host”
We create a new AWS Application Load Balancer and get this error message when the second listener is created Error: Error creating LB Listener: ValidationError: ‘arn:aws:elasticloadbalancing:….’ must be in ARN format make sure the region and AWS profile are correctly set for the new listener config.
When we test a Chef cookbook in Chef Test Kitchen and get the error message TypeError ——— no implicit conversion of String into Integer Check if all attribute references have the “node” keyword in front of them.
In the previous post, Learn Kubernetes part 2 – NGINX Ingress Controller, we have deployed a web application and exposed it via the kubernetes/ingress-nginx ingress controller. In this exercise we will use Traefik, another popular proxy server. Traefik is widely used for multiple reasons: it is easier to configure, can automatically generate and renew SSL …
Continue reading “Learn Kubernetes part 3 – Traefik Ingress Controller”
Large organizations need to control the incoming traffic to the Kubernetes cluster. The most secure way is to use an ingress controller and create an ingress to channel all incoming traffic to the cluster. In Learn Kubernetes part 1 – Web application in a Kubernetes cluster we have created a simple web application pod and …
Continue reading “Learn Kubernetes part 2 – NGINX Ingress Controller”
This is the official Kubernetes dashboard, and for security reasons currently it is not recommended to use, but we can still use it in our local cluster to inspect the resources. The latest installation information is at https://kubernetes.io/docs/tasks/access-application-cluster/web-ui-dashboard/ Launch the Kubernetes Dashboard To launch the Kubernetes Dashboard in your cluster execute the command Create a …
Use the ingress-nginx Kubernetes plugin to troubleshoot the Kubernetes Ingress-Nginx. Install krew, the Kubernetes plugin manager. See https://github.com/kubernetes-sigs/krew See Kubernetes Ingress-Nginx Troubleshooting made Easy with kubectl plugins Verify the cluster you are connected to To switch to another cluster Get the address of the cluster Get the list of pods Forward a port to the …
This is a tutorial to script a simple web application deployment in an enterprise grade Kubernetes cluster that you can follow on your Macintosh. You only need to install Docker and enable Kubernetes. The frontend of the web application is represented by an NGINX container that listens on port 80 and returns the NGINX default …
Continue reading “Learn Kubernetes part 1 – Web application in a Kubernetes cluster”
Helm takes values that we pass into the Helm deployments and transforms a template (also known as a chart) to Kubernetes resources. It is a wrapper around Kubernetes resources. It calls kubectl in the background to create the resources on the fly.
For security reasons it is not a good practice to create individual load balancers for each service. The safer way is to create one application load balancer outside of the cluster and launch ingress controller NGINX containers to proxy the traffic to the individual services. Ingress “Ingress exposes HTTP and HTTPS routes from outside the …