kubernetes service

service工作模式

• userspace 1.1-
• iptables 1.10-
• ipvs 1.11+

service类型

• ClusterIP
• NodePort
• LoadBalancer
• ExternalName

资源记录

SVC_NAME.NS_NAME.DOMAIN.LTD.

svc.cluster.local.

redis.default.svc.cluster.local.

service yaml

redis-svc.yaml

apiVersion: v1
kind: Service
metadata:
  name: redis
  namespace: default
spec:
  selector:
    app: redis
    role: logstor
  clusterIP: 10.254.0.97
  type: ClusterIP
  ports:
  - port: 6379
    targetPort: 6379

myapp-svc.yaml

apiVersion: v1
kind: Service
metadata:
  name: myapp
  namespace: default
spec:
  selector:
    app: myapp
    release: canary
  type: NodePort
  ports:
  - port: 80
    targetPort: 80
    nodePort: 30080

while true;do curl http://192.168.0.13:30080/hostname.html;sleep 1;done
while true;do curl http://192.168.0.13:30080;sleep 1;done

会话保持

kubectl patch service myapp -p '{"spec":{"sessionAffinity":"ClientIP"}}'
kubectl patch service myapp -p '{"spec":{"sessionAffinity":"None"}}'

无头service myapp-svc-headless.yaml

apiVersion: v1
kind: Service
metadata:
  name: myapp-svc
  namespace: default
spec:
  selector:
    app: myapp
    release: canary
  clusterIP: None
  ports:
  - port: 80
    targetPort: 80

dig -t A myapp.default.svc.cluster.local. @10.254.0.10