Docker or Kubernetes Which ? When ? in Proxmox

November 23, 2024

1. Our requirement :

Is to get a Ubuntu Server as a container

2. How we will do this :

What we will do is Start with docker show 3 ways to do this Then we will do this with Kubernetes first a single pod then show 2 ways to scale up this requirement

Finally we will look at a High Availability Kubernetes with nodes in Berlin Germany, London England, and New York

We will do all this in our Proxmox server

3. Here’s a quick comparison to help decide:

Docker

Best for: Individual application containerization and smaller-scale projects.
Simplicity: Easy to use for running and managing containers.
Resource Requirements: Lightweight, minimal overhead.
Platform Independent: Ensures consistent behavior across development, testing, and production environments.
Use Case: Local development, testing, and single-node deployments.

Kubernetes

Best for: Orchestrating containers across multiple nodes in large-scale, production-grade systems.
Scalability: Automates scaling, networking, and load balancing.
Automation: Handles networking, load balancing, and resource management seamlessly.5. Ideal for Microservices: Perfect for complex, 4. distributed systems requiring multi-container coordination.
Use Case: Enterprise-level applications needing high availability, fault tolerance, and microservices orchestration.

4. Creating a simple Ubuntu server using Docker

4.1 Created from Docker Commands

Pull the Ubuntu Image:

docker pull ubuntu:latest

Run a Container with Bash Terminal:

docker run -it ubuntu:latest bash

TRunning commands in the container :

ls -la /home

apt update

apt install curl

4.2 Using a docker compose file to create the same container

Run this Command :

nano compose.yaml

Put this in the file :

version: '3.9'

services:
  ubuntu-server:
    image: ubuntu:latest
    container_name: ubuntu_server
    volumes:
      - ./data:/opt/data
    stdin_open: true # Keeps the container interactive
    tty: true        # Allocates a pseudo-TTY

Run the following commands

# Start the conatiner in detached mode
docker-compose up -d
# To access the container, use:
docker exec -it ubuntu_server bash
 
# Now Inside the container run these commands:
lsb_release -a

ls -la /opt

touch test1.txt

5. Kubernetes

5.1 create the cluster

This is beyond the scope of this video however for completeness sake we have included Appendix A with the procedure

5.2 From the Primary Master Node Create a Kubernetes manifest to create the same container

Run thie command :

nano nginx-manifest.yaml

Put this in the file

apiVersion: v1
kind: Namespace
metadata:
  name: nginx
---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: nginx-deployment
  namespace: nginx
spec:
  selector:
    matchLabels:
      app: nginx
  replicas: 3
  template:
    metadata:
      labels:
        app: nginx
    spec:
      containers:
      - name: nginx
        image: nginx:1.14.2
        ports:
        - containerPort: 80
---
apiVersion: v1
kind: Service
metadata:
  name: nginx
  namespace: nginx
  labels:
    run: nginx
spec:
  ports:
    - port: 80
  selector:
    app: nginx
---
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: nginx
  namespace: nginx
  annotations:
    ingress.kubernetes.io/ssl-redirect: "false"
spec:
  rules:
  - http:
      paths:
      - path: /
        pathType: Prefix
        backend:
          service:
            name: nginx
            port:
              number: 80

Run these commands :

kubectl create namespace nginx

#  Apply the manifest:
kubectl apply -f nginx-manifest.yaml -n nginx

# Confirm the resources were created:
kubectl get pods -n nginx
kubectl get all -n nginx

# we now have 3 replicas (instances) running we want 5

# Scale up the instances to 5 using this command :
kubectl scale deployment nginx-deployment --replicas=5 --namespace=nginx

# Confirm that we have 5 replicas resources were created:
kubectl get pods -n nginx
kubectl get all -n nginx

Appendix A Creating the Kubernetes Cluster

1 create the cluster

1.1 The Primary Master node London England

Run these commands :

sudo su -

mkdir /opt/k3s -p

cd /opt/k3s/

nano Primary-Master-Node-ip-60.sh

Put this in the file:

#! /bin/bash
# Primary-Master-Node-ip-80.sh
#######################
# Primary Master Node #
#######################
# IP Address: 10.154.2.60
# FQDN: London
# User ID: nickm
# K3s Token: K10e132fef7618115b243c442ab7841f4dd093f73a266d972a97a057b8d94461d9f::server:87e8469573f644feda130f74d3c05d51
# 
node_name="London"
curl -sfL https://get.k3s.io | K3S_NODE_NAME=${node_name} sh -s - server --cluster-init --write-kubeconfig-mode=644
echo "Please run this command and update token in config.yaml"
echo "cat /var/lib/rancher/k3s/server/node-token"

Run these commands :

chmod 775 Primary-Master-Node-ip-60.sh

./Primary-Master-Node-ip-60.sh

# get the Security Token
cat /var/lib/rancher/k3s/server/node-token
# use this to update the following Shell Scripts

To verify this Node and other Nodes were created run this command on this server evry time :

kubectl get nodes

1.2 The Second Master node Berlin Germany

Run these command

sudo su -

mkdir /opt/k3s -p

cd /opt/k3s/

nano Second-Master-Node-ip-61.sh

Put this in the file:

#! /bin/bash
# Second-Master-Node-ip-61.sh
#######################
# Second Master Node #
#######################
# IP Address: 10.154.2.61
# FQDN: Berlin
# User ID: nickm
# Primary Master Node IP Address: 10.154.2.60
# K3s Token: K1099-PLEASE-REPLACE-THIS-WITH-THE-SERVERS-TOKEN-6a22c
# 
k3s_token="K1099-PLEASE-REPLACE-THIS-WITH-THE-SERVERS-TOKEN-6a22c"
k3s_url="https://10.154.2.60:6443"
node_name="Berlin"
curl -sfL https://get.k3s.io | K3S_TOKEN=${k3s_token} K3S_NODE_NAME=${node_name} sh -s - server --server ${k3s_url} --write-kubeconfig-mode=644

echo "Please run this command and update token in config.yaml"
echo "cat /var/lib/rancher/k3s/server/node-token"

Run these commands

chmod 775 Second-Master-Node-ip-61.sh

./Second-Master-Node-ip-61.sh

1.3 The Third Master node New York

Run these commands

sudo su -

mkdir /opt/k3s -p

cd /opt/k3s/

nano Third-Worker-Node-ip-93.sh

Put this in the file:

#! /bin/bash
# Third-Master-Node-ip-62.sh
#######################
# Third Master Node #
#######################
# IP Address: 10.154.2.62
# FQDN: New_York
# User ID: nickm
# Primary Master Node IP Address: 10.154.2.60
# K3s Token: K1099-PLEASE-REPLACE-THIS-WITH-THE-SERVERS-TOKEN-6a22c
# 
k3s_token="K1099-PLEASE-REPLACE-THIS-WITH-THE-SERVERS-TOKEN-6a22c"
k3s_url="https://10.154.2.60:6443"
node_name="New_York"
curl -sfL https://get.k3s.io | K3S_TOKEN=${k3s_token} K3S_NODE_NAME=${node_name} sh -s - server --server ${k3s_url} --write-kubeconfig-mode=644

echo "Please run this command and update token in config.yaml"
echo "cat /var/lib/rancher/k3s/server/node-token"

Run these commands

chmod 775 Third-Worker-Node-ip-93.sh

./Third-Worker-Node-ip-93.sh

1.4 The Worker node

Run these commands

sudo su -

mkdir /opt/k3s -p

cd /opt/k3s/

nano First-Worker-Node-ip-63.sh

Put this in the file:

#! /bin/bash
# First-Worker-Node-ip-63.sh
#######################
# First Worker Node #
#######################
# IP Address: 10.154.2.63
# FQDN: Worker
# User ID: nickm
# Primary Master Node IP Address: 10.154.2.60
# 
k3s_token="K1099-PLEASE-REPLACE-THIS-WITH-THE-SERVERS-TOKEN-6a22c"
k3s_url="https://10.154.2.60:6443"
node_name="Worker"
curl -sfL https://get.k3s.io | K3S_URL=${k3s_url} K3S_TOKEN=${k3s_token} K3S_NODE_NAME=${node_name} sh -

Run these commands

chmod 775 First-Worker-Node-ip-63.sh

./First-Worker-Node-ip-63.sh

1. Our requirement :

2. How we will do this :

3. Here’s a quick comparison to help decide:

Docker

Kubernetes

4. Creating a simple Ubuntu server using Docker

** 4.1 Created from Docker Commands**

4.2 Using a docker compose file to create the same container

5. Kubernetes

5.1 create the cluster

This is beyond the scope of this video however for completeness sake we have included Appendix A with the procedure

5.2 From the Primary Master Node Create a Kubernetes manifest to create the same container

Appendix A Creating the Kubernetes Cluster

1 create the cluster

1.1 The Primary Master node London England

1.2 The Second Master node Berlin Germany

1.3 The Third Master node New York

1.4 The Worker node

4.1 Created from Docker Commands