Quick recap for network. Details can click the title link or check the official doc.
1. create
# target port: listening port inside container
# port: service internal port
# NodePort: expose external port
kubectl expose deployment nginx --name nginx-svc --port 8081 --target-port 80 --type [NodePort|ClusterIP]
# --dry-run=client -oyaml
2. curl
# on node
curl localhost:NodePort # NodePort
curl NODE_IP:NodePort # NodePort
curl SVC_IP:SVC_Port # ClusterIP
# in other pod (ClusterIP)
curl SVC_NAME:SVC_Port
curl SVC_IP:SVC_Port
3. check
-
endpoints- tells Kubernetes where to forward the traffic from the service.
-
port-forward- Creating a network tunnel between your local machine and the Kubernetes cluster
# endpoints IP -> Pod IP
k get endpoints
# port-forward
kubectl port-forward TYPE/NAME LOCAL_PORT:REMOTE_PORT
1. Yaml File
Notice:
ingressClassName: if there is noingressclass, create one first, if no IngressClass exists, the ingress resource will not be handled by any controller, and your routes won’t work. Pls check official doc
spec:
ingressClassName: nginx # used for ingress controller
rules:
- host: "foo.bar.com" # domain name
http:
paths:
- pathType: Prefix
path: "/bar" # http://domain/path
backend:
service:
name: service1 # svc
port:
number: 80 # svc port
2. Check
Pod IP -> endpoint IP -> ingress IP
# domain name should add into /etc/hosts file with the ingress IP
curl DOMAINNAME:SVC_PORT
1. Fields
- act on pods:
namespacepodSelector
- type:
ingress.from&egress.to - traffic flow source/destination pods
namespaceSelectorpodSelectorports
and the yaml file here.
Notice:
Cross Node DNS should add the full name in Fully Qualified Domain Name (FQDN) format for a service:
<service-name>.<namespace-name>.svc.cluster.local
more details check official doc