Create a deployment and expose service port

kubectl create deployment json-server --image=hieuvpn/lap:8 -r 2
kubectl expose deployment json-server --type=LoadBalancer --name=json-server --port=8092

#allow pods run on master-node
kubectl taint nodes --all node-role.kubernetes.io/master-
kubectl taint nodes --all  node-role.kubernetes.io/control-plane-

#kubectl taint node master-node node-role.kubernetes.io/master=:NoSchedule

expose port 8080

‘ name: json-server
‘ ports:
‘ - containerPort: 80
‘   protocol: TCP
‘ resources: {}

Limit resouce

‘ resources:
‘  limits:
‘   cpu: 200m
‘   memory: 300M
‘  requests:
‘   cpu: 50m
‘   memory: 200M

Volume mount

‘ resources: {}
‘ volumeMounts:
‘ - mountPath: /data
‘   name: jsrv
‘   subPath: json-server

‘ terminationGracePeriodSeconds: 30
‘ volumes:
‘ - name: jsrv
‘     persistentVolumeClaim:
‘       claimName: json-server

Liveness Probe

‘        resources: {}
‘        livenessProbe:
‘          failureThreshold: 3
‘          httpGet:
‘            path: /livez
‘            port: https
‘            scheme: HTTPS
‘          periodSeconds: 10
‘          successThreshold: 1
‘          timeoutSeconds: 1
‘        readinessProbe:
‘          failureThreshold: 3
‘          exec:
‘            command:
‘            - /bin/bash
‘            - c
‘            - /ready.sh

‘          initialDelaySeconds: 20
‘          periodSeconds: 10
‘          successThreshold: 1
‘          timeoutSeconds: 1

Public IP

clusterIPs:
- 10.110.15.54
externalIPs:
- 69.30.241.22

Longhorn

curl -sSfL https://raw.githubusercontent.com/longhorn/longhorn/v1.4.0/scripts/environment_check.sh | bash
#kernel version (uname -r) must be the same on all nodes

kubectl apply -f https://raw.githubusercontent.com/longhorn/longhorn/v1.4.0/deploy/prerequisite/longhorn-iscsi-installation.yaml
kubectl apply -f https://raw.githubusercontent.com/longhorn/longhorn/v1.4.0/deploy/prerequisite/longhorn-nfs-installation.yaml

kubectl apply -f https://raw.githubusercontent.com/longhorn/longhorn/v1.4.0/deploy/longhorn.yaml
web portal = service longhorn-frontend
Create Volume, PV/PVC, mount /dev/sdb /mnt/longhorn
MetricServer

wget https://github.com/kubernetes-sigs/metrics-server/releases/latest/download/components.yaml -O metrics-server-components.yaml

wget  https://github.com/kubernetes-sigs/metrics-server/releases/latest/download/high-availability.yaml -O metrics-server-ha.yaml

kubectl apply -f  metrics-server-ha.yaml

edit the deployment, add - --kubelet-insecure-tls
Execute pod command
kubectl exec mysql-set-0 -- sh -c "mysql --defaults-extra-file=/etc/mysql/conf.d/my.key <  /etc/mysql/conf.d/init.sql"
kubectl exec mysql-set-0 -i -- bash < mysql-set0.cmd

Restart Pod
kubectl delete pod  mysql-set-0
Restart Deployment
kubectl rollout restart deployment json-server



Docker rmi --prune

crictl -r /run/containerd/containerd.sock rmi --prune

docker system prune --volumes


Copy file from host to pods

kubectl cp /tmp/foo <some-namespace>/<some-pod>:/tmp/bar