TIPS Kubernates Project

Master Server Ruoli (alta disponibilità quindi consigliato isolarli a Vcenter o in macchine protette).

1- Gateway
2- Scheduling
3- Manager

Nodi mutevoli in base al ruolo che prendendo.

I Nodi master vengono chiamati Control plane vedi openshift: Al cui interno: KubeApiserver, etcd, control Manager, scheduler.

- Nei Nodi: Kubelet -> docker o contaniner manager locale / Network-proxy 

Master - Json (Manifest) -> Nodo Kubelet - Docker Engine

Al di fuori del cluster che comunica solo e solamente con il Master. KubeCtl (Android, IOS)

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kube-controller-manager / cloud-controller-manager (espansione verso il cloud)

Le immagini vanno referenziate solo e solamente da Docker.

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IGNORARE

Prereq project:

- Virtual Machine Linux - Docker Framework

Oracle Linux 8:

Problema pods c'e' installato un "coso" alternativo docker: https://www.ibm.com/docs/en/eam/4.2?topic=questions-troubleshooting-tips#uninstall_podman

 yum remove buildah skopeo podman containers-common atomic-registries docker container-tools -y 

Docker Framework: https://docs.docker.com/engine/install/centos/

Creazione un utente di gestione (simil ansible)

[root@minikube01 ~]# cd /etc
[root@minikube01 etc]# vi group

Add user generic es. admin in /etc/group gruppo docker

minikube config set driver docker
minikube start

kubectl port-forward service/hello-minikube 8080:8080 --address='0.0.0.0'

In caso di riavvio della macchina da utente admin:

http://10.2.2.35:7080/

minikube start

Links:

https://amalgjose.com/2021/06/08/how-to-configure-kubernetes-port-forward-bind-to-0-0-0-0-instead-of-default-127-0-0-1/
https://docs.docker.com/engine/install/centos/
https://minikube.sigs.k8s.io/docs/start/

-- Oracle Linux 9.3 --

sudo yum update
sudo yum install yum-utils
sudo yum-config-manager --add-repo https://download.docker.com/linux/centos/docker-ce.repo
sudo yum install docker-ce docker-ce-cli containerd.io
sudo systemctl start docker
sudo systemctl enable docker

Test:

sudo docker --version

https://docs.oracle.com/en/learn/ol-kube/#introduction

sudo tee /etc/yum.repos.d/kubernetes.repo <<EOF
[kubernetes]
name=Kubernetes
baseurl=https://packages.cloud.google.com/yum/repos/kubernetes-el7-\$basearch
enabled=1
gpgcheck=1
repo_gpgcheck=1
gpgkey=https://packages.cloud.google.com/yum/doc/yum-key.gpg https://packages.cloud.google.com/yum/doc/rpm-package-key.gpg
EOF

sudo yum install -y kubelet kubeadm kubectl