Say I have a service that isn't hosted on Kubernetes. I also have an ingress controller and cert-manager set up on my kubernetes cluster.
Because it's so much simpler and easy to use kubernetes ingress to control access to services, I wanted to have a kubernetes ingress that points to a non-kubernetes service.
For example, I have a service that's hosted at https://10.0.40.1:5678
(ssl required, but self signed certificate) and want to access at service.example.com
.
You can do it by manual creation of Service and Endpoint objects for your external server.
Objects will looks like that:
apiVersion: v1
kind: Service
metadata:
name: external-ip
spec:
ports:
- name: app
port: 80
protocol: TCP
targetPort: 5678
clusterIP: None
type: ClusterIP
---
apiVersion: v1
kind: Endpoints
metadata:
name: external-ip
subsets:
- addresses:
- ip: 10.0.40.1
ports:
- name: app
port: 5678
protocol: TCP
Then, you can create an Ingress object which will point to Service external-ip
with port 80
:
apiVersion: extensions/v1beta1
kind: Ingress
metadata:
name: external-service
spec:
rules:
- host: service.example.com
http:
paths:
- backend:
serviceName: external-ip
servicePort: 80
path: /
If your external service has a dns entry configured on it, you can use kubernetes externalName service.
If your external service has a dns entry configured on it, you can use kubernetes externalName service.
---
apiVersion: v1
kind: Service
metadata:
name: my-service
namespace: prod
spec:
type: ExternalName
externalName: myexternal.http.service.com
---
apiVersion: extensions/v1beta1
kind: Ingress
metadata:
name: externalNameservice
namespace: prod
spec:
rules:
- host: service.example.com
http:
paths:
- backend:
serviceName: my-service
servicePort: 80
path: /
In this way, kubernetes create cname record my-service pointing to myexternal.http.service.com
In this way, kubernetes create cname record my-service pointing to myexternal.http.service.com
There is no way you can specify in the ingress configuration that a certain rule should divert traffic to a service hosted outside the cluster.
Your only choice here is to create a reverse proxy service and inside your cluster and let it act as a middleman between the user and the real service.
Asimple approach -
var httpProxy = require('http-proxy');
var proxy = httpProxy.createProxyServer(options);
http.createServer(function(req, res) {
proxy.web(req, res, { target: 'http://mytarget.com:8080' });
});