k8s cheatsheet

default-tls-store.yaml

apiVersion: traefik.containo.us/v1alpha1
kind: TLSStore
metadata:
  name: default
  namespace: dev

spec:
  defaultCertificate:
    secretName: whoami-secret

NOTES.sh

#!/usr/bin/env bash
# -*- coding: utf-8 -*-

# get k8s contexts
kubectl config get-contexts -o name --no-headers

# get k8s current context
kubectl config current-context

# generate self signed SSL cert - oneliner
openssl req -x509 -newkey rsa:4096 -sha256 -days 3650 -nodes \
    -keyout server.key -out server.crt -subj "/CN=kubernetes.127.0.0.1.nip.io" \
    -addext "subjectAltName=DNS:kubernetes.127.0.0.1.nip.io,DNS:whoami.127.0.0.1.nip.io,IP:127.0.0.1"

# generate self signed SSL cert based on openssl.conf file
# openssl req -nodes -new -x509 -keyout server.key -out server.crt -config openssl.conf -days 365

# save SSL cert into k8s secret
kubectl create secret generic whoami-secret --from-file=tls.crt=./server.crt --from-file=tls.key=./server.key --namespace dev

# replace k8s secret - TRICKY
kubectl create secret generic whoami-secret \
    --namespace dev \
    -o yaml --save-config --dry-run=client \
    --from-file=tls.crt=./server.crt --from-file=tls.key=./server.key | kubectl apply -f -

# Add certificate to Trusted CAs on Windows
sudo.exe certutil -addstore root ./server.crt

# Install usbipd (USB device support in WSL 2)
winget.exe install --interactive --exact dorssel.usbipd-win

# Get WSL version
cat /proc/version



### Kubernetes: detecting the installed version of nginx ingress
# namespace of your nginx ingress
ingress_ns="ingress-nginx"

# find running pod
podname=$(kubectl get pods -n $ingress_ns -l app.kubernetes.io/name=ingress-nginx --field-selector=status.phase==Running -o jsonpath='{.items[0].metadata.name}'
)

echo "pod name: $podname"

# invoke controller with version flag
kubectl exec -it -n $ingress_ns $podname -- /nginx-ingress-controller --version

traefik-debug.yaml

apiVersion: helm.cattle.io/v1
kind: HelmChartConfig
metadata:
  name: traefik
  namespace: kube-system
spec:
  valuesContent: |-
    additionalArguments:
      - "--log.level=DEBUG"