Can the same hostname be used in different namespaces in kubernetes? - kubernetes

Question

I want to use my hostname as test.com in first namespace and example.com/demo in another namespace. However i am unable to do that since (in my opinion) the nginx-ingress controller always points to the first website (example.com). My nginx-ingress controller is running in the default namespace
#namespace prod
kind: Ingress
apiVersion: extensions/v1beta1
metadata:
name: ingress
namespace: production
annotations:
nginx.ingress.kubernetes.io/proxy-body-size: 20m
spec:
rules:
- host: example.com
http:
paths:
- path: /static
backend:
serviceName: app-svc
servicePort: 80
- path: /
backend:
serviceName: app-svc
servicePort: 8000
tls:
- hosts:
- example.com
secretName: cert
status:
loadBalancer:
ingress:
- ip: xx.xxx.xx.xxx
#namespace dev
kind: Ingress
apiVersion: extensions/v1beta1
metadata:
name: test-ingress
namespace: dev-env
annotations:
nginx.ingress.kubernetes.io/proxy-body-size: 20m
spec:
rules:
- host: example.com
http:
paths:
- path: /static
backend:
serviceName: app-svc
servicePort: 80
- path: /demo
backend:
serviceName: app-svc
servicePort: 8000
tls:
- hosts:
- example.com
secretName: cert
status:
loadBalancer:
ingress:
- ip: xx.xxx.xx.xxx

Answer 1

You can use the same hostname/domain, but in order to access distinct backend services, you have to define distinct paths, in your case you can do something like this:
#namespace prod
kind: Ingress
apiVersion: extensions/v1beta1
metadata:
name: test-ingress
namespace: prod-env
annotations:
nginx.ingress.kubernetes.io/proxy-body-size: 20m
spec:
rules:
- host: example.com
http:
paths:
- path: /prod/static
backend:
serviceName: app-svc
servicePort: 80
- path: /prod/
backend:
serviceName: app-svc
servicePort: 8000
tls:
- hosts:
- example.com
secretName: selfsigned-cert
status:
loadBalancer:
ingress:
- ip: 80.180.31.153
#namespace dev
kind: Ingress
apiVersion: extensions/v1beta1
metadata:
name: test-ingress
namespace: dev-env
annotations:
nginx.ingress.kubernetes.io/proxy-body-size: 20m
spec:
rules:
- host: example.com
http:
paths:
- path: /dev/static
backend:
serviceName: app-svc
servicePort: 80
- path: /demo
backend:
serviceName: app-svc
servicePort: 8000
tls:
- hosts:
- example.com
secretName: selfsigned-cert
status:
loadBalancer:
ingress:
- ip: 80.180.31.153
Like this you have:
example.com/prod/static -> points to app-svc:80 on prod-env namespace
example.com/prod/ -> points to app-svc:8000 on prod-env namespace
example.com/dev/static -> points to app-svc:8000 on dev-env namespace
example.com/demo -> points to app-svc:8000 on dev-env namespace
If you need to preserve the url after host, you should add a subdomain for each namespace:
dev.example.com/static -> points to app-svc:80 on prod-env namespace
prod.example.com/static -> points to app-svc:8000 on dev-env namespace
In order for this one to work you have to have defined this as an A record in your domain DNS administration, pointing at the same IP as your loadBalancer (80.180.31.153 in this case):
example.com A -> 80.180.31.153 (optional)
dev.exmaple.com A -> 80.180.31.153
prod.example.com A -> 80.180.31.153
or the easiest one:
*.example.com A -> 80.180.31.153