Skip to content

Latest commit

 

History

History
282 lines (229 loc) · 9.09 KB

mixed-cluster-ingress.md

File metadata and controls

282 lines (229 loc) · 9.09 KB
Raw

Using http ingress routing in a mixed cluster

Prerequisites

  1. First, deploy a cluster with both Windows & Linux nodes. See the Kubernetes Windows Walkthrough for a step by step example.
  2. Install Helm, the Kubernetes package manager

Steps

Configure Helm

helm init --upgrade --node-selectors "beta.kubernetes.io/os=linux"

Set up NGINX

helm install --name nginx-ingress `
    --set controller.nodeSelector."beta\.kubernetes\.io\/os"=linux `
    --set defaultBackend.nodeSelector."beta\.kubernetes\.io\/os"=linux `
     --set rbac.create=true `
    stable/nginx-ingress
helm install --name nginx-ingress \
    --set controller.nodeSelector."beta\.kubernetes\.io\/os"=linux \
    --set defaultBackend.nodeSelector."beta\.kubernetes\.io\/os"=linux \
    --set rbac.create=true \
    stable/nginx-ingress

This will return output like this

NAME:   nginx-ingress
LAST DEPLOYED: Thu Aug 23 11:51:11 2018
NAMESPACE: default
STATUS: DEPLOYED

RESOURCES:
==> v1/Pod(related)
NAME                                            READY  STATUS             RESTARTS  AGE
nginx-ingress-controller-76c4d5cf59-zj7vb       0/1    ContainerCreating  0         2s
nginx-ingress-default-backend-69c6b65b46-d64nd  0/1    ContainerCreating  0         2s

==> v1/ConfigMap
NAME                      DATA  AGE
nginx-ingress-controller  1     2s

==> v1/Service
NAME                           TYPE          CLUSTER-IP    EXTERNAL-IP  PORT(S)                     AGE
nginx-ingress-controller       LoadBalancer  10.0.165.193  <pending>    80:32186/TCP,443:31319/TCP  2s
nginx-ingress-default-backend  ClusterIP     10.0.219.85   <none>       80/TCP                      2s

==> v1beta1/Deployment
NAME                           DESIRED  CURRENT  UP-TO-DATE  AVAILABLE  AGE
nginx-ingress-controller       1        1        1           0          2s
nginx-ingress-default-backend  1        1        1           0          2s

==> v1beta1/PodDisruptionBudget
NAME                           MIN AVAILABLE  MAX UNAVAILABLE  ALLOWED DISRUPTIONS  AGE
nginx-ingress-controller       1              N/A              0                    2s
nginx-ingress-default-backend  1              N/A              0                    2s


NOTES:
The nginx-ingress controller has been installed.
It may take a few minutes for the LoadBalancer IP to be available.
You can watch the status by running 'kubectl --namespace default get services -o wide -w nginx-ingress-controller'

An example Ingress that makes use of the controller:

  apiVersion: extensions/v1beta1
  kind: Ingress
  metadata:
    annotations:
      kubernetes.io/ingress.class: nginx
    name: example
    namespace: foo
  spec:
    rules:
      - host: www.example.com
        http:
          paths:
            - backend:
                serviceName: exampleService
                servicePort: 80
              path: /
    # This section is only required if TLS is to be enabled for the Ingress
    tls:
        - hosts:
            - www.example.com
          secretName: example-tls

If TLS is enabled for the Ingress, a Secret containing the certificate and key must also be provided:

  apiVersion: v1
  kind: Secret
  metadata:
    name: example-tls
    namespace: foo
  data:
    tls.crt: <base64 encoded cert>
    tls.key: <base64 encoded key>
  type: kubernetes.io/tls

Create a web server and service

Copy the YAML below into a file called iis.yaml.

apiVersion: apps/v1
kind: Deployment
metadata:
  name: iis-1803
  labels:
    app: iis-1803
spec:
  replicas: 1
  template:
    metadata:
      name: iis-1803
      labels:
        app: iis-1803
    spec:
      containers:
      - name: iis
        image: microsoft/iis:windowsservercore-1803
        ports:
          - containerPort: 80
      nodeSelector:
        "beta.kubernetes.io/os": windows
  selector:
    matchLabels:
      app: iis-1803
---
apiVersion: v1
kind: Service
metadata:
  name: iis
spec:
  type: ClusterIP
  ports:
  - protocol: TCP
    port: 80
  selector:
    app: iis-1803

If you're using Windows Server version 1803, you can use it as-is. If you're using 1709, replace all the instances of 1803 with 1709.

Now, run kubectl create -f iis.yaml

Check that the web server is running with kubectl get pod, and look for iis-1803-....

kubectl get pod
NAME                                             READY     STATUS    RESTARTS   AGE
iis-1803-8b7fdd569-nvzx8                         1/1       Running   0          4m
nginx-ingress-controller-57cbbfcb7c-fgtdn        1/1       Running   0          17m
nginx-ingress-default-backend-69c6b65b46-zjc2c   1/1       Running   0          17m

If it's not ready, check again in a bit. The first time this is run, the container image pull may take up to 20 minutes. kubectl describe pod ... will give more details on progress.

It's also good to confirm the service is up with kubectl describe svc iis, and that there is at least one endpoint listed.

kubectl describe svc iis
Name:              iis
Namespace:         default
Labels:            <none>
Annotations:       <none>
Selector:          app=iis-1803
Type:              ClusterIP
IP:                10.0.7.142
Port:              <unset>  80/TCP
TargetPort:        80/TCP
Endpoints:         10.240.0.143:80
Session Affinity:  None
Events:            <none>

Create the ingress rule

Now that the pod and service are running, it's time to create the ingress.

Copy this YAML to a file called ingress.yaml

apiVersion: extensions/v1beta1
kind: Ingress
metadata:
  annotations:
    kubernetes.io/ingress.class: nginx
  name: iis-ingress
  namespace: default
spec:
  rules:
    - host: test.ogfg.link
      http:
        paths:
          - backend:
              serviceName: iis
              servicePort: 80
            path: /

Then edit to your needs. Be sure to set host to a DNS name that you are able to manage. Create the ingress rule with kubectl create -f ingress.yaml

Now, it's a good time to test the ingress rule from inside the cluster. Run kubectl get svc nginx-ingress-controller and look for CLUSTER-IP

kubectl get svc nginx-ingress-controller
NAME                       TYPE           CLUSTER-IP    EXTERNAL-IP     PORT(S)                      AGE
nginx-ingress-controller   LoadBalancer   10.0.71.219   13.77.176.117   80:32040/TCP,443:30669/TCP   31m

SSH to a Linux node in the cluster, and run curl -H 'host:<hostname for ingress rule>' http://<CLUSTER-IP>

$ curl -H 'Host: test.ogfg.link' http://10.0.71.219                                                                                   
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1" />
<title>IIS Windows Server</title>

This should return the web page contents, not an error.

Update DNS

Now, you need to make sure that the external IP for the nginx-ingress-controller is registered in your DNS zone.

First, get the external IP for the ingress controller with kubectl describe svc nginx-ingress-controller

kubectl describe svc nginx-ingress-controller
Name:                     nginx-ingress-controller
Namespace:                default
Labels:                   app=nginx-ingress
                          chart=nginx-ingress-0.11.1
                          component=controller
                          heritage=Tiller
                          release=nginx-ingress
Annotations:              <none>
Selector:                 app=nginx-ingress,component=controller,release=nginx-ingress
Type:                     LoadBalancer
IP:                       10.0.71.219
LoadBalancer Ingress:     13.77.176.117
Port:                     http  80/TCP
TargetPort:               80/TCP
NodePort:                 http  32040/TCP
Endpoints:                10.240.0.56:80
Port:                     https  443/TCP
TargetPort:               443/TCP
NodePort:                 https  30669/TCP
Endpoints:                10.240.0.56:443
Session Affinity:         None
External Traffic Policy:  Cluster
Events:
  Type    Reason                Age   From                Message
  ----    ------                ----  ----                -------
  Normal  EnsuringLoadBalancer  24m   service-controller  Ensuring load balancer
  Normal  EnsuredLoadBalancer   23m   service-controller  Ensured load balancer

LoadBalancer Ingress is the external IP. Create a DNS A record with a matching hostname (or wildcard) and that external IP.

If you're using Azure DNS, then you can set this in your DNS zone with:

az network dns record-set a add-record -n test -g <resource group containing dns zone> --zone-name <DNS zone> --ipv4-address <IP of ingress service>

Now, you should be able to access your Windows web server running at http://hostname