# OpenShift 3.11

1. Environment
+ CentOS 7
+ Docker
+ https://docs.docker.com/engine/install/centos/
+ sudo groupadd docker
+ sudo usermod -aG docker $USER
+ (relogin)
+ docker ps (no sudo required)
2. Install OpenShift
+ vi /etc/docker/daemon.json

    {
        "insecure-registries": [
            "172.30.0.0/16"
        ]
    }

+ docker network inspect -f "{{range .IPAM.Config}}{{.Subnet}}{{end}}" bridge
+ 172.17.0.0/16
+ restart docker
+ systemctl daemon-reload
+ systemctl restart docker
+ download and install OpenShift
+ curl -OL https://github.com/openshift/origin/releases/download/v3.11.0/openshift-origin-client-tools-v3.11.0-0cbc58b-linux-64bit.tar.gz
+ sudo tar zxvf openshift-origin-client-tools-v3.11.0-0cbc58b-linux-64bit.tar.gz --strip-components=1 -C /usr/local/bin openshift-origin-client-tools-v3.11.0-0cbc58b-linux-64bit/oc
+ sudo tar zxvf openshift-origin-client-tools-v3.11.0-0cbc58b-linux-64bit.tar.gz --strip-components=1 -C /usr/local/bin openshift-origin-client-tools-v3.11.0-0cbc58b-linux-64bit/kubectl
+ oc version
+ kubectl
+ create cluster
+ ip a
+ 192.168.56.104
+ oc cluster up --public-hostname=192.168.56.104
+ curl https://192.168.56.104:8443 -k
+ (optional) login as admin
+ oc login -u system:admin
+ oc whoami
+ kubectl cluster-info
+ kubectl get nodes -o wide
+ oc adm registry (twice)
3. Create New Application
+ (optional) create new project
+ oc new-project dev
+ oc projects (show all projects)
+ oc project myproject (switch to myproject default project)
+ oc project dev (switch to dev project)
+ create new app
+ oc new-app nginxinc/nginx-unprivileged
+ check and wait
+ oc status
+ oc logs dc/nginx-unprivileged
+ oc get pods (till build pod completed and main pod running)
+ oc get svc
+ CLUSTER-IP, PORT
+ curl http://CLUSTER-IP:PORT
+ expose a route
+ oc expose svc/nginx-unprivileged
+ oc get route
+ curl http://nginx-unprivileged-dev.192.168.56.104.nip.io
4. Change
+ baseline
+ oc get dc -o yaml > dc.yaml
+ oc delete dc/nginx-unprivileged
+ oc get dc,po
+ no resources
+ curl http://nginx-unprivileged-dev.192.168.56.104.nip.io
+ error html
+ oc apply -f dc.yaml
+ curl http://nginx-unprivileged-dev.192.168.56.104.nip.io
+ normal response
+ using host-path
+ dc -> pvc -> pv0001 ~ pv0100
+ using nfs
+ dc -> pvc -> pv -> nfs
5. Lifecycle
+ clean project
+ oc delete all -l app=nginx-unprivileged
+ oc delete project dev (don't remove the default myproject)
+ restart cluster
+ oc cluster down
+ oc cluster up
+ rebuild cluster
+ oc cluster down
+ rm -rf ~/.kube
+ for i in $(mount | grep openshift | awk '{print $3}'); do sudo umount $i; done
+ sudo rm -rf openshift.local.clusterup
+ oc cluster up --public-hostname=192.168.56.104
6. Reference
+ https://blog.miniasp.com/post/2020/10/11/Install-OpenShift-Origin-OKD-311-on-Ubuntu-Linux
# NFS
+ oc whoami
+ system:admin
+ cat pv.yml

apiVersion: v1
kind: PersistentVolume
metadata:
  name: pv1
spec:
  capacity:
    storage: 5Gi
  accessModes:
  - ReadWriteMany
  nfs:
    path: /var/nfsshare
    server: server.nfs.org

+ oc apply -f pv.yml
+ oc get pv/pv1
+ status: Available
+ cat pvc.yml

apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: pvc1
spec:
  accessModes:
    - ReadWriteMany
  resources:
    requests:
      storage: 1Gi
  volumeName: pv1

+ oc apply -f pvc.yml
+ oc get pvc/pvc1
+ status: Bound
+ https://www.howtoforge.com/nfs-server-and-client-on-centos-7
+ https://docs.openshift.com/container-platform/3.11/install_config/persistent_storage/persistent_storage_nfs.html#nfs-volume-security
+ https://docs.openshift.com/container-platform/3.11/install_config/persistent_storage/pod_security_context.html#user-id
# Customize app with NFS
+ cat pod.yml

kind: Pod
apiVersion: v1
metadata:
  name: pod1
  labels:
    app: nginx
spec:
  containers:
    - name: nginx
      image: docker.io/nginx
      ports:
      - containerPort: 80
        protocol: TCP
      volumeMounts:
      - mountPath: "/var/log/nginx"
        name: volume1
  volumes:
    - name: volume1
      persistentVolumeClaim:
        claimName: pvc1

+ oc apply -f pod.yml
+ oc get pod/pod1
+ ready: 1+
+ status: Running
+ cat svc.yml

apiVersion: v1
kind: Service
metadata:
  name: svc1
spec:
  selector:
    app: nginx
  ports:
  - port: 8080
    protocol: TCP
    targetPort: 80

+ oc apply -f svc.yml
+ oc get svc/svc1
+ CLUSTER-IP, 8080
+ curl http://CLUSTER-IP:8080
+ CONNECTION refused
+ oc cluster down
+ oc cluster up
+ curl http://CLUSTER-IP:8080
+ CONNECTION OK
+ oc exec -it pod1 \-\- tail /var/log/nginx/access.log
+ oc expose svc/svc1
+ curl http://svc1-dev.192.168.56.104.nip.io
# CodeReady Containers
+ crc start / stop
+ https://console.redhat.com/openshift/create/local
# NFS Server on MacOS
+ MacOS
+ mkdir ~/nfsshare
+ sudo vi /etc/exports
+ /Users/david/nfsshare -mapall=david -network 192.168.108 -mask 255.255.254.0
+ sudo nfsd checkexports
+ sudo nfsd start
+ nfsd status
+ Firewall
+ Allow 192.168.108.1/23 -> 172.16.4.232 111/2049 TCP/UDP
+ Linux Client
+ sudo yum install nfs-utils
+ mkdir /mnt/nfs
+ sudo mount -t nfs 172.16.4.232:/Users/david/nfsshare /mnt/nfs/
+ df
+ sudo umount /mnt/nfs
+ https://docstore.mik.ua/orelly/unix3/mac/ch03_10.htm
+ https://superuser.com/questions/1196409/how-to-restart-nfsd-service-on-macos
+ https://www.freebsd.org/cgi/man.cgi?exports(5)