[쿠버네티스 네트워크] ClusterIP와 SessionAffinity 실습

kubectl create deploy --image=gasbugs/http-go http-go --port=8080 --dry-run=client -o yaml

kubectl create deploy --image=gasbugs/http-go http-go --port=8080 --dry-run=client -o yaml > http-go-deploy.yaml

http-go-deploy.yaml

apiVersion: v1
kind: Service
metadata:
  name: http-go-svc
spec:
  selector:
    run: http-go
  ports:
    - protocol: TCP
      port: 80
      targetPort: 8080
---
apiVersion: apps/v1
kind: Deployment
metadata:
  creationTimestamp: null
  labels:
    run: http-go
  name: http-go
spec:
  replicas: 1
  selector:
    matchLabels:
      run: http-go
  strategy: {}
  template:
    metadata:
      creationTimestamp: null
      labels:
        run: http-go
    spec:
      containers:
      - image: gasbugs/http-go
        name: http-go
        ports:
        - containerPort: 8080
        resources: {}
status: {}

nano http-go-deploy.yaml

kubectl create -f http-go-deploy.yaml

kubectl get all

kubectl get pods -o wide

kubectl describe svc

inkunyoung@cloudshell:~/kubeservice (k8s-inflearn)$ kubectl describe svc
Name:              http-go-svc
Namespace:         default
Labels:            <none>
Annotations:       cloud.google.com/neg: {"ingress":true}
Selector:          run=http-go
Type:              ClusterIP
IP Family Policy:  SingleStack
IP Families:       IPv4
IP:                10.108.3.150
IPs:               10.108.3.150
Port:              <unset>  80/TCP
TargetPort:        8080/TCP
>> Endpoints:         10.104.2.5:8080
Session Affinity:  None
Events:            <none>

kubectl scale deploy http-go --replicas=5

kubectl get pod -w

imkunyoung@cloudshell:~/kubeservice (k8s-inflearn)$ kubectl get pods -o wide
NAME                       READY   STATUS    RESTARTS   AGE     IP           NODE                                                NOMINATED NODE   READINESS GATES
http-go-85cf4fd86b-7wcn8   1/1     Running   0          76s     10.104.2.6   gke-my-first-cluster-1-default-pool-a0f2cf43-zs3g   <none>           <none>
http-go-85cf4fd86b-8qh56   1/1     Running   0          3m35s   10.104.2.5   gke-my-first-cluster-1-default-pool-a0f2cf43-zs3g   <none>           <none>
http-go-85cf4fd86b-ktv6b   1/1     Running   0          76s     10.104.0.8   gke-my-first-cluster-1-default-pool-a0f2cf43-m3k4   <none>           <none>
http-go-85cf4fd86b-s2t45   1/1     Running   0          76s     10.104.1.5   gke-my-first-cluster-1-default-pool-a0f2cf43-20cx   <none>           <none>
http-go-85cf4fd86b-wx5sv   1/1     Running   0          76s     10.104.1.4   gke-my-first-cluster-1-default-pool-a0f2cf43-20cx   <none>           <none>

imkunyoung@cloudshell:~/kubeservice (k8s-inflearn)$  kubectl describe svc http-go-svc
Name:              http-go-svc
Namespace:         default
Labels:            <none>
Annotations:       cloud.google.com/neg: {"ingress":true}
Selector:          run=http-go
Type:              ClusterIP
IP Family Policy:  SingleStack
IP Families:       IPv4
IP:                10.108.3.150
IPs:               10.108.3.150
Port:              <unset>  80/TCP
TargetPort:        8080/TCP
Endpoints:         10.104.0.8:8080,10.104.1.4:8080,10.104.1.5:8080 + 2 more...
Session Affinity:  None
Events:            <none>

kubectl edit svc http-go-svc

imkunyoung@cloudshell:~/kubeservice (k8s-inflearn)$ kubectl get svc http-go-svc -o yaml
apiVersion: v1
kind: Service
metadata:
  annotations:
    cloud.google.com/neg: '{"ingress":true}'
  creationTimestamp: "2023-07-25T18:35:03Z"
  name: http-go-svc
  namespace: default
  resourceVersion: "2967358"
  uid: c478a5aa-9165-4f71-94eb-c8542dd57793
spec:
  clusterIP: 10.108.3.150
  clusterIPs:
  - 10.108.3.150
  internalTrafficPolicy: Cluster
  ipFamilies:
  - IPv4
  ipFamilyPolicy: SingleStack
  ports:
  - port: 80
    protocol: TCP
    targetPort: 8080
  selector:
    run: http-go
 >>  sessionAffinity: ClientIP
  sessionAffinityConfig:
    clientIP:
      timeoutSeconds: 10800
  type: ClusterIP
status:
  loadBalancer: {}

kubectl run -it --rm --image=busybox bash

imkunyoung@cloudshell:~/kubeservice (k8s-inflearn)$ kubectl run -it --rm --image=busybox bash

If you don't see a command prompt, try pressing enter.

/ # 
/ # 
/ # wget -O- -q 10.108.3.150
Welcome! http-go-85cf4fd86b-7wcn8
/ # wget -O- -q 10.108.3.150
Welcome! http-go-85cf4fd86b-7wcn8
/ # wget -O- -q 10.108.3.150
Welcome! http-go-85cf4fd86b-7wcn8
/ # wget -O- -q 10.108.3.150
Welcome! http-go-85cf4fd86b-7wcn8
/ # wget -O- -q 10.108.3.150
Welcome! http-go-85cf4fd86b-7wcn8
/ # wget -O- -q 10.108.3.150
Welcome! http-go-85cf4fd86b-7wcn8
/ # wget -O- -q 10.108.3.150
Welcome! http-go-85cf4fd86b-7wcn8

-- 같은 ip로 유지 (ClientIP)

Reference:

difference-clusterip-nodeport-loadbalancer-kubernetes