Deployment pod cannot connect ClusterIP service - docker

Question

I try to expose my server IP by using Ingress.
The server is an Express.js app. It listens at http://localhost:5000 locally when without docker.
Here are my Kubernetes config files:
server-deployment.yaml
apiVersion: v1
apiVersion: apps/v1
kind: Deployment
metadata:
name: server-deployment
spec:
replicas: 1
selector:
matchLabels:
component: server
template:
metadata:
labels:
component: server
spec:
containers:
- name: server
image: hongbomiao/hongbomiao-server:latest
ports:
- containerPort: 5000
env:
- name: NODE_ENV
value: development
server-cluster-ip-service.yaml
kind: Service
metadata:
name: server-cluster-ip-service
spec:
type: ClusterIP
selector:
component: server
ports:
- port: 5000
targetPort: 5000
ingress-service.yaml
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
name: ingress-service
annotations:
nginx.ingress.kubernetes.io/rewrite-target: /
spec:
rules:
- http:
paths:
- path: /
pathType: Prefix
backend:
service:
name: server-cluster-ip-service
port:
number: 5000
I got my minikube IP by
➜ minikube ip
192.168.64.12
When I open 192.168.64.12 in my browser, I got 502 Bad Gateway.
I got some debug idea after reading https://cloud.google.com/kubernetes-engine/docs/how-to/exposing-apps#kubectl-apply. Here is what I have tried:
➜ kubectl get service
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 5h34m
server-cluster-ip-service ClusterIP 10.102.5.161 <none> 5000/TCP 4h39m
➜ kubectl get pods
NAME READY STATUS RESTARTS AGE
server-deployment-bc6777445-pj59f 1/1 Running 0 4h39m
➜ kubectl exec -it server-deployment-bc6777445-pj59f -- sh
/app # apk add --no-cache curl
...
/app # curl 10.102.5.161:5000
curl: (28) Failed to connect to 10.102.5.161 port 5000: Operation timed out
It seems my deployment pod has issue connecting ClusterIP service now. Any help will be nice!

Answer 1

It turns out the issue is caused by my VPN.
I didn't change anything for the Kubernetes config in my question.
Also, letting the Express.js server explicitly listen at 0.0.0.0 is not necessary neither.
(Note #David Maze's comment under the question about 0.0.0.0 is still valuable)
const app = express()
.use(bodyParser.json())
.use(express.static(path.join(__dirname, '../dist')))
app.listen(5000); // This just works. No need explicitly change to app.listen(5000, '0.0.0.0');
At the time of writing, I was in China. To get rid of the VPN while still using Kubenetes / minikube, I found a way and posted it at GitHub here.
After turning off the VPN with this workaround solution, everything just works.
Copy my solution using minikube in China here:
Step 1 - Download the Aliyun version minikube
curl -Lo minikube https://kubernetes.oss-cn-hangzhou.aliyuncs.com/minikube/releases/v1.14.2/minikube-darwin-amd64 && chmod +x minikube && sudo mv minikube /usr/local/bin/
Note: You can find if there is a new version to replace v1.14.2 in the command above at https://github.com/AliyunContainerService/minikube/wiki#%E5%AE%89%E8%A3%85minikube
Step 2 - Start the minikube
minikube start --image-mirror-country cn \
--driver=hyperkit \
--iso-url=https://kubernetes.oss-cn-hangzhou.aliyuncs.com/minikube/iso/minikube-v1.15.0.iso \
--registry-mirror=https://xxxxxxxx.mirror.aliyuncs.com
Note 1: You can find latest minikube version at https://github.com/kubernetes/minikube/blob/master/CHANGELOG.md, then replace v1.15.0 in the command above to newer version.
However, Aliyun's minikube version is a little behind. To verify if a new version exists, you can replace the version in the URL of https://kubernetes.oss-cn-hangzhou.aliyuncs.com/minikube/iso/minikube-v1.15.0.iso to different new versions, such as v1.15.1, and then open it in the browser.
Note 2: For the xxxxxxxx in the command above, you can find yours at
https://cr.console.aliyun.com/cn-hangzhou/instances/mirrors
(Need register an Aliyun account first)
Note 3: You can pass more parameters to this Aliyun version minikube start, check at https://github.com/AliyunContainerService/minikube/wiki#%E5%90%AF%E5%8A%A8
In my case, I am using the driver hyperkit on macOS, and Aliyun's iso-url, registry-mirror to speed up.