Static IPs

This example demonstrates how to assign a static-ip to an Ingress on GCE.

Prerequisites

You need a TLS cert and a test HTTP service for this example. You will also need to make sure you Ingress targets exactly one Ingress controller by specifying the ingress.class annotation, and that you have an ingress controller running in your cluster.

Acquiring a static IP

In GCE, static IP belongs to a given project until the owner decides to release it. If you create a static IP and assign it to an Ingress, deleting the Ingress or tearing down the GKE cluster will not delete the static IP. You can check the static IPs you have as follows

$ gcloud compute addresses list --global
NAME                     REGION  ADDRESS          STATUS
test-ip                          35.186.221.137   RESERVED

$ gcloud compute addresses list
NAME                      REGION       ADDRESS          STATUS
test-ip                                35.186.221.137   RESERVED
test-ip                   us-central1  35.184.21.228    RESERVED

Note the difference between a regional and a global static ip. Only global static-ips will work with Ingress. If you don't already have an IP, you can create it

$ gcloud compute addresses create test-ip --global
Created [https://www.googleapis.com/compute/v1/projects/kubernetesdev/global/addresses/test-ip].
---
address: 35.186.221.137
creationTimestamp: '2017-01-31T10:32:29.889-08:00'
description: ''
id: '9221457935391876818'
kind: compute#address
name: test-ip
selfLink: https://www.googleapis.com/compute/v1/projects/kubernetesdev/global/addresses/test-ip
status: RESERVED

Assigning a static IP to an Ingress

You can now add the static IP from the previous step to an Ingress, by specifying the kubernetes.io/global-static-ip-name annotation, the example yaml in this directory already has it set to test-ip

$ kubectl create -f gce-static-ip-ingress.yaml
ingress "static-ip" created

$ gcloud compute addresses list test-ip
NAME     REGION       ADDRESS         STATUS
test-ip               35.186.221.137  IN_USE
test-ip  us-central1  35.184.21.228   RESERVED

$ kubectl get ing
NAME        HOSTS     ADDRESS          PORTS     AGE
static-ip   *         35.186.221.137   80, 443   1m

$ curl 35.186.221.137 -Lk
CLIENT VALUES:
client_address=10.180.1.1
command=GET
real path=/
query=nil
request_version=1.1
request_uri=http://35.186.221.137:8080/
...

Retaining the static IP

You can test retention by deleting the Ingress

$ kubectl delete -f gce-static-ip-ingress.yaml
ingress "static-ip" deleted

$ kubectl get ing
No resources found.

$ gcloud compute addresses list test-ip --global
NAME     REGION       ADDRESS         STATUS
test-ip               35.186.221.137  RESERVED

Promote ephemeral to static IP

If you simply create a HTTP Ingress resource, it gets an ephemeral IP

$ kubectl create -f gce-http-ingress.yaml
ingress "http-ingress" created

$ kubectl get ing
NAME           HOSTS     ADDRESS         PORTS     AGE
http-ingress   *         35.186.195.33   80        1h

$ gcloud compute forwarding-rules list
NAME                                           REGION       IP_ADDRESS      IP_PROTOCOL  TARGET
k8s-fw-default-http-ingress--32658fa96c080068               35.186.195.33   TCP          k8s-tp-default-http-ingress--32658fa96c080068

Note that because this is an ephemeral IP, it won't show up in the output of gcloud compute addresses list.

If you either directly create an Ingress with a TLS section, or modify a HTTP Ingress to have a TLS section, it gets a static IP.

$ kubectl patch ing http-ingress -p '{"spec":{"tls":[{"secretName":"tls-secret"}]}}'
"http-ingress" patched

$ kubectl get ing
NAME           HOSTS     ADDRESS         PORTS     AGE
http-ingress   *         35.186.195.33   80, 443   1h

$ gcloud compute addresses list
NAME                                           REGION       ADDRESS          STATUS
k8s-fw-default-http-ingress--32658fa96c080068               35.186.195.33    IN_USE

4.3 KiB Raw Blame History