kubernetes DNS列出服务的所有ip

Question

我有一个pod列表，像这样:

❯ kubectl get pods -l app=test-pod                                                                                                                              (base)
NAME                               READY   STATUS    RESTARTS   AGE
test-deployment-674667c867-jhvg4   1/1     Running   0          14m
test-deployment-674667c867-ssx6h   1/1     Running   0          14m
test-deployment-674667c867-t4crn   1/1     Running   0          14m

我有一个服务

kubectl get services                                                                                                                          (base)
NAMESPACE     NAME                                TYPE        CLUSTER-IP       EXTERNAL-IP   PORT(S)                        AGE
default       test-service                        ClusterIP   10.100.4.138     <none>        4000/TCP                       15m

我执行dns查询:

❯ kubectl exec -ti test-deployment-674667c867-jhvg4  -- /bin/bash                                                                                               (base)
root@test-deployment-674667c867-jhvg4:/# busybox nslookup test-service
Server:     10.100.0.10
Address:    10.100.0.10:53
Name:   test-service.default.svc.cluster.local
Address: 10.100.4.138

我的配置:

apiVersion: apps/v1
kind: Deployment
metadata:
name: test-deployment
spec:
replicas: 3
selector:
matchLabels:
app: test-pod
template:
metadata:
labels:
app: test-pod
spec:
containers:
- name: python-http-server
image: python:2.7
command: ["/bin/bash"]
args: ["-c", "echo " Hello from $(hostname)" > index.html; python -m SimpleHTTPServer 80"]
ports:
- name: http
containerPort: 80
kind: Service
apiVersion: v1
metadata:
name: test-service
spec:
selector:
app: test-pod
ports:
- protocol: TCP
port: 4000
targetPort: http

我如何通过dns查询获得所有pod的ip地址列表?

理想情况下，我想执行一个名称的nslookup，并在一个列表中获得所有pod的ip列表。

Answer 1

您必须使用带有选择器的无头服务。它返回pod的ip地址。

看这里:https://kubernetes.io/docs/concepts/services-networking/service/headless-services

.spec。clusterIP必须为"None">