ssh -L <port>:localhost:<port> username@k8s-shell

> kubectl create namespace kooper
namespace/kooper created

> kubectl get namespace kooper -o yaml
apiVersion: v1
kind: Namespace
metadata:
  annotations:
    cattle.io/status: '{"Conditions":[{"Type":"ResourceQuotaInit","Status":"True","Message":"","LastUpdateTime":"2023-06-25T13:35:36Z"},{"Type":"InitialRolesPopulated","Status":"True","Message":"","LastUpdateTime":"2023-06-25T13:35:36Z"}]}'

apiVersion: v1
kind: Namespace
metadata:
  name: kooper

> kubectl config set-context --current --namespace=kooper
Context "k8s-class" modified.

apiVersion: v1
kind: Pod
metadata:
  name: cowsay
  namespace: kooper
spec:
  restartPolicy: Never
  containers:
  - name: cowsay
    image: rancher/cowsay

> kubectl logs pod/cowsay​
  _
<   >
 -
        \   ^__^
         \  (oo)\_______
            (__)\       )\/\
                ||----w |
                ||     || 

> kubectl delete pod/cowsay
pod "cowsay" deleted

apiVersion: v1
kind: Pod
metadata:
  name: cowsay
  namespace: kooper
spec:
  restartPolicy: Never
  containers:
  - name: cowsay
    image: rancher/cowsay
    command:
    - cowsay
    - Mooooo

apiVersion: v1
kind: Pod
metadata:
  name: cowsay
  namespace: kooper
spec:
  restartPolicy: Never
  containers:
  - name: cowsay
    image: rancher/cowsay
    command:
    - cowsay
    - Mooooo
  - name: whalesay
    image: docker/whalesay
    command:
    - cowsay
    - Howdy

> kubectl logs cowsay
Defaulted container "cowsay" out of: cowsay, whalesay
 ________
< Mooooo >
 --------
        \   ^__^
         \  (oo)\_______
            (__)\       )\/\
                ||----w |
                ||     ||
> kubectl logs cowsay -c whalesay
 _______
< Howdy >
 -------
    \
     \
      \
                    ##        .
              ## ## ##       ==
           ## ## ## ##      ===
       /""""""""""""""""___/ ===
  ~~~ {~~ ~~~~ ~~~ ~~~~ ~~ ~ /  ===- ~~~
       \______ o          __/
        \    \        __/
          \____\______/ 

> kubectl describe pod cowsay
Name:         cowsay
Namespace:    kooper
Priority:     0
Node:         k8s-class-worker-01/192.168.2.42
Start Time:   Sun, 25 Jun 2023 09:52:44 -0500
Labels:       <none>
Annotations:  <none>
Status:       Failed
...
Events:
  Type     Reason     Age   From               Message
  ----     ------     ----  ----               -------
  Normal   Scheduled  5s    default-scheduler  Successfully assigned kooper/cowsay to k8s-class-worker-01
  Normal   Pulling    5s    kubelet            Pulling image "rancher/cowsay"
  Normal   Pulled     5s    kubelet            Successfully pulled image "rancher/cowsay" in 321.252759ms
  Normal   Created    5s    kubelet            Created container cowsay
  Warning  Failed     5s    kubelet            Error: failed to start container "cowsay": Error response from daemon: failed to create shim task: OCI runtime create failed: runc create failed: unable to start container process: exec: "Mooooo": executable file not found in $PATH: unknown

> kubectl get sc
NAME                   PROVISIONER                                               RECLAIMPOLICY   VOLUMEBINDINGMODE   ALLOWVOLUMEEXPANSION   AGE
csi-cinder-sc-delete   cinder.csi.openstack.org                                  Delete          Immediate           true                   18h
csi-cinder-sc-retain   cinder.csi.openstack.org                                  Retain          Immediate           true                   18h
nfs-taiga (default)    cluster.local/nfs-taiga-nfs-subdir-external-provisioner   Retain          Immediate           true                   17h

> kubectl get pv
NAME                                       CAPACITY   ACCESS MODES   RECLAIM POLICY   STATUS   CLAIM             STORAGECLASS   REASON   AGE
pvc-4ff2a331-466b-41c4-9c4a-18734c70badd   128Mi      RWO            Retain           Bound    traefik/traefik   nfs-taiga               18h

apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: kooper-pvc
spec:
  storageClassName: manual
  accessModes:
    - ReadWriteMany
  resources:
    requests:
      storage: 1Gi

> kubectl apply -f pvc1.yaml
persistentvolumeclaim/kooper-pvc created
> kubectl get pv
NAME                                       CAPACITY   ACCESS MODES   RECLAIM POLICY   STATUS   CLAIM             STORAGECLASS   REASON   AGE
pvc-4ff2a331-466b-41c4-9c4a-18734c70badd   128Mi      RWO            Retain           Bound    traefik/traefik   nfs-taiga               18h
> kubectl delete -f pvc1.yaml
persistentvolumeclaim "kooper-pvc" deleted

apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: kooper-pvc
spec:
  storageClassName: nfs-taiga
  accessModes:
    - ReadWriteMany
  resources:
    requests:
      storage: 1Gi

apiVersion: v1
kind: Pod
metadata:
  name: pod-with-pvc
spec:
  restartPolicy: Never
  volumes:
  - name: data
    persistentVolumeClaim:
      claimName: kooper-pvc
  containers:
  - name: ubuntu
    image: ubuntu
    command: ["sleep", "3600"]
    volumeMounts:
    - name: data
      mountPath: /data

> kubectl exec -ti pod-with-pvc -- bash
root@pod-with-pvc:/#

apiVersion: v1
kind: Pod
metadata:
  name: nginx
spec:
  volumes:
  - name: data
    persistentVolumeClaim:
      claimName: kooper-pvc
  initContainers:
  - name: create-index-html
    image: busybox:1.28
    command:
      - sh
      - -c
      - echo "<html><body>Created $(date)</body></html>">/data/index.html
    volumeMounts:
    - name: data
      mountPath: /data
  containers:
  - name: nginx
    image: nginx:1.14.2
    ports:
    - containerPort: 80
    livenessProbe:
      httpGet:
        port: 80
    readinessProbe:
      httpGet:
        port: 80
      initialDelaySeconds: 5
      periodSeconds: 10
    volumeMounts:
    - name: data
      mountPath: /usr/share/nginx/html

> kubectl port-forward pod nginx 8888:80Forwarding from 127.0.0.1:8888 -> 80
Forwarding from [::1]:8888 -> 80

apiVersion: apps/v1
kind: Deployment
metadata:
  name: nginx
  labels:
    app: nginx
spec:
  replicas: 3
  selector:
    matchLabels:
      app: nginx
  template:
    metadata:
      labels:
        app: nginx
    # copied from before
    spec:
      volumes:
      - name: data
        persistentVolumeClaim:
          claimName: kooper-pvc
      initContainers:
      - name: create-index-html
        image: busybox:1.28
        command:
          - sh
          - -c
          - echo "<html><body>Created $(date)</body></html>">/data/index.html
        volumeMounts:
        - name: data
          mountPath: /data
      containers:
      - name: nginx
        image: nginx:1.14.2
        ports:
        - containerPort: 80
        livenessProbe:
          httpGet:
            port: 80
        readinessProbe:
          httpGet:
            port: 80
          initialDelaySeconds: 5
          periodSeconds: 10
        volumeMounts:
        - name: data
          mountPath: /usr/share/nginx/html

> kubectl scale deployment/nginx --replicas=0deployment.apps/nginx scaled

apiVersion: v1
kind: Service
metadata:
  name: nginx
spec:
  selector:
    app: nginx
  ports:
    - protocol: TCP
      port: 80
      targetPort: 80

apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: nginx
spec:
  rules:
  - host: kooper.k8s-class.ncsa.cloud
    http:
      paths:
      - path: /
        pathType: ImplementationSpecific
        backend:
          service:
            name: nginx
            port:
              number: 80

> helm create nginx
Creating nginx 

# This is the chart version. This version number should be incremented each time you make changes
# to the chart and its templates, including the app version.
# Versions are expected to follow Semantic Versioning (https://semver.org/)
version: 0.1.0

# This is the version number of the application being deployed. This version number should be
# incremented each time you make changes to the application. Versions are not expected to
# follow Semantic Versioning. They should reflect the version the application is using.
# It is recommended to use it with quotes.
appVersion: "1.16.0"

replicaCount: 3

ingress:
  enabled: true
  hosts:
    - host: kooper.k8s-class.ncsa.cloud
      paths:
        - path: /
          pathType: ImplementationSpecific

> helm template . -f custom.yaml
---
# Source: nginx/templates/serviceaccount.yaml
apiVersion: v1
kind: ServiceAccount
...
spec:
  containers:
    - name: wget
      image: busybox
      command: ['wget']
      args: ['release-name-nginx:80']
  restartPolicy: Never

> helm install nginx . -f custom.yaml
NAME: nginx
LAST DEPLOYED: Sun Jun 25 22:45:54 2023
NAMESPACE: kooper
STATUS: deployed
REVISION: 1
NOTES:
1. Get the application URL by running these commands:
  http://kooper.k8s-class.ncsa.cloud/

> helm ls
NAME 	NAMESPACE	REVISION	UPDATED                                	STATUS  	CHART      	APP VERSION
nginx	kooper   	1       	2023-06-25 22:45:54.045250697 -0500 CDT	deployed	nginx-0.1.0	1.16.0

{{- if and .Values.persistence.enabled (not .Values.persistence.existingClaim) }}
kind: PersistentVolumeClaim
apiVersion: v1
metadata:
  name: {{ template "nginx.fullname" . }}-data
  labels:
    {{ include "nginx.labels" . | nindent 4 }}
spec:
  accessModes:
    - ReadWriteMany
  resources:
    requests:
      storage: {{ .Values.persistence.size | quote }}
  {{- if .Values.persistence.storageClass }}
  storageClassName: {{ .Values.persistence.storageClass }}
  {{- end -}}
{{- end }}

# Dependencies for chart. Some of the dependencies are only installed if they
# are enabled.
dependencies:
- name: postgresql
  version: ~8.9
  repository:  https://raw.githubusercontent.com/bitnami/charts/pre-2022/bitnami
  condition: postgres.enabled

# start with the name of the chart (or alias)
postgresql:
  ## enabled should the postgresql chart be installed as well. If not make
  ## sure that the other values are provied to get access to the database.
  enabled: true

  ## postgresqlUsername is the initial user added to the system. 
  # postgresqlUsername: postgres

  ## postgresqlPassword the password for postgresqlUsername
  postgresqlPassword: supersecret

  # need more space
  persistence:
    size: 20Gi

apiVersion: apps/v1
kind: Deployment
metadata:
...
spec:
  ...
  template:
    ...
    spec:
      ...
      initContainers:
        - name: check-postgresql
          image: "ncsa/checks:1.0.1"
          env:
            - name: PGHOST
              value: {{ .Release.Name }}-postgresql
            - name: PGPORT
              value: "5432"
            - name: PGUSER
              value: {{ .Values.postgresql.postgresqlUsername | default "postgres" | quote }}
            - name: PGPASSWORD
              valueFrom:
                secretKeyRef:
                  name: {{ .Release.Name }}-postgresql
                  key: postgresql-password