Deployment is a method of converting images to containers and then allocating those images to pods in the Kubernetes cluster.
This also helps in setting up the application cluster which includes deployment of service, pod, replication controller and replica set.
The cluster can be set up in such a way that the applications deployed on the pod can communicate with each other.
In this setup, we can have a load balancer setting on top of one application diverting traffic to a set of pods and later they communicate to backend pods.
The communication between pods happen via the service object built in Kubernetes.
Ngnix Load Balancer Yaml File
apiVersion: v1
kind: Service
metadata:
name: oppv-dev-nginx
labels:
k8s-app: omni-ppv-api
spec:
type: NodePort
ports:
- port: 8080
nodePort: 31999
name: omninginx
selector:
k8s-app: appname
component: nginx
env: dev
kind: Service
metadata:
name: oppv-dev-nginx
labels:
k8s-app: omni-ppv-api
spec:
type: NodePort
ports:
- port: 8080
nodePort: 31999
name: omninginx
selector:
k8s-app: appname
component: nginx
env: dev
Ngnix Replication Controller Yaml
apiVersion: v1
kind: ReplicationController
metadata:
name: appname
spec:
replicas: replica_count
template:
metadata:
name: appname
labels:
k8s-app: appname
component: nginx
env: env_name
spec:
nodeSelector:
resource-group: oppv
containers:
- name: appname
image: IMAGE_TEMPLATE
imagePullPolicy: Always
ports:
- containerPort: 8080
resources:
requests:
memory: "request_mem"
cpu: "request_cpu"
limits:
memory: "limit_mem"
cpu: "limit_cpu"
env:
- name: BACKEND_HOST
value: oppv-env_name-node:3000
kind: ReplicationController
metadata:
name: appname
spec:
replicas: replica_count
template:
metadata:
name: appname
labels:
k8s-app: appname
component: nginx
env: env_name
spec:
nodeSelector:
resource-group: oppv
containers:
- name: appname
image: IMAGE_TEMPLATE
imagePullPolicy: Always
ports:
- containerPort: 8080
resources:
requests:
memory: "request_mem"
cpu: "request_cpu"
limits:
memory: "limit_mem"
cpu: "limit_cpu"
env:
- name: BACKEND_HOST
value: oppv-env_name-node:3000
Frontend Service Yaml File
apiVersion: v1
kind: Service
metadata:
name: appname
labels:
k8s-app: appname
spec:
type: NodePort
ports:
- name: http
port: 3000
protocol: TCP
targetPort: 3000
selector:
k8s-app: appname
component: nodejs
env: dev
kind: Service
metadata:
name: appname
labels:
k8s-app: appname
spec:
type: NodePort
ports:
- name: http
port: 3000
protocol: TCP
targetPort: 3000
selector:
k8s-app: appname
component: nodejs
env: dev
Frontend Replication Controller Yaml File
apiVersion: v1
kind: ReplicationController
metadata:
name: Frontend
spec:
replicas: 3
template:
metadata:
name: frontend
labels:
k8s-app: Frontend
component: nodejs
env: Dev
spec:
nodeSelector:
resource-group: oppv
containers:
- name: appname
image: IMAGE_TEMPLATE
imagePullPolicy: Always
ports:
- containerPort: 3000
resources:
requests:
memory: "request_mem"
cpu: "limit_cpu"
limits:
memory: "limit_mem"
cpu: "limit_cpu"
env:
- name: ENV
valueFrom:
configMapKeyRef:
name: appname
key: config-env
kind: ReplicationController
metadata:
name: Frontend
spec:
replicas: 3
template:
metadata:
name: frontend
labels:
k8s-app: Frontend
component: nodejs
env: Dev
spec:
nodeSelector:
resource-group: oppv
containers:
- name: appname
image: IMAGE_TEMPLATE
imagePullPolicy: Always
ports:
- containerPort: 3000
resources:
requests:
memory: "request_mem"
cpu: "limit_cpu"
limits:
memory: "limit_mem"
cpu: "limit_cpu"
env:
- name: ENV
valueFrom:
configMapKeyRef:
name: appname
key: config-env
Backend Service Yaml File
apiVersion: v1
kind: Service
metadata:
name: backend
labels:
k8s-app: backend
spec:
type: NodePort
ports:
- name: http
port: 9010
protocol: TCP
targetPort: 9000
selector:
k8s-app: appname
component: play
env: dev
kind: Service
metadata:
name: backend
labels:
k8s-app: backend
spec:
type: NodePort
ports:
- name: http
port: 9010
protocol: TCP
targetPort: 9000
selector:
k8s-app: appname
component: play
env: dev
Backed Replication Controller Yaml File
apiVersion: v1
kind: ReplicationController
metadata:
name: backend
spec:
replicas: 3
template:
metadata:
name: backend
labels:
k8s-app: beckend
component: play
env: dev
spec:
nodeSelector:
resource-group: oppv
containers:
- name: appname
image: IMAGE_TEMPLATE
imagePullPolicy: Always
ports:
- containerPort: 9000
command: [ "./docker-entrypoint.sh" ]
resources:
requests:
memory: "request_mem"
cpu: "request_cpu"
limits:
memory: "limit_mem"
cpu: "limit_cpu"
volumeMounts:
- name: config-volume
mountPath: /app/vipin/play/conf
volumes:
- name: config-volume
configMap:
name: appname
kind: ReplicationController
metadata:
name: backend
spec:
replicas: 3
template:
metadata:
name: backend
labels:
k8s-app: beckend
component: play
env: dev
spec:
nodeSelector:
resource-group: oppv
containers:
- name: appname
image: IMAGE_TEMPLATE
imagePullPolicy: Always
ports:
- containerPort: 9000
command: [ "./docker-entrypoint.sh" ]
resources:
requests:
memory: "request_mem"
cpu: "request_cpu"
limits:
memory: "limit_mem"
cpu: "limit_cpu"
volumeMounts:
- name: config-volume
mountPath: /app/vipin/play/conf
volumes:
- name: config-volume
configMap:
name: appname