Gloo Edge for Knative

For the purpose of running Knative, Gloo Edge can function as a complete replacement for Istio (supporting all documented Knative features), requiring less resource usage and operational overhead.

This guide walks you through installing Gloo Edge and Knative using either glooctl (the Gloo Edge command line) or Helm.

Installing the Gloo Edge Knative Ingress on Kubernetes

These directions assume you’ve prepared your Kubernetes cluster appropriately. Full details on setting up your Kubernetes cluster can be found here. You can install Gloo Edge Knative Ingress using using glooctl or through Helm. Helm is the recommended method for installing in a Production environment.

Installing on Kubernetes with glooctl

Before you begin, make sure that you install glooctl, the Gloo Edge command line tool (CLI).

Using glooctl will install Knative Serving components to the knative-serving namespace if it does not already exist in your cluster and install Gloo Edge’s Knative Ingress. The Knative installation is a modified version of the Knative Serving manifest with the dependencies on Istio removed.

If you will be installing Gloo Edge Knative Ingress on a cluster that already has the Knative Serving components deployed, you can use the flag --install-knative=false to skip the Knative installation. More details can be found in the Knative installation guide.

Once your Kubernetes cluster is up and running, run the following command to deploy the Gloo Edge Ingress to the gloo-system namespace and Knative-Serving components to the knative-serving namespace:

glooctl install knative

Installing on Kubernetes with Helm

This is the recommended method for installing Gloo Edge to your production environment as it offers rich customization to the Gloo Edge control plane and the proxies Gloo Edge manages. This guide assumes that you are using Helm version 3, and have already installed the Helm client on your local machine.

First, make sure you have Knative installed. If you do not, you can install Knative components without Gloo Edge using glooctl:

glooctl install knative -g

Once the installation is complete, you can validate by checking the namespace knative-serving.

kubectl get all -n knative-serving

Now let’s install Gloo Edge. If needed, add the Gloo Edge repository to the list of known chart repositories and perform a repository update:

helm repo add gloo https://storage.googleapis.com/solo-public-helm
helm repo update

In the values for the Helm chart, you are going to set gateway.enabled to false, settings.integrations.knative.enabled to true, and configure the version of Knative at the path settings.integrations.knative.version. You can do this either by creating a values.yaml file with the proper settings or by defining the settings in line.

First you need to know what version of Knative you are running. You can find this by running the following command:

kubectl describe namespace knative-serving

In the output, look for the version value in the Annotations section:

Name:         knative-serving
Labels:       istio-injection=enabled
              serving.knative.dev/release=v0.10.0
Annotations:  gloo.solo.io/glooctl_install_info: {"version":"0.10.0","monitoring":false,"eventing":false,"eventingVersion":"0.10.0"}
              kubectl.kubernetes.io/last-applied-configuration:
                {"apiVersion":"v1","kind":"Namespace","metadata":{"annotations":{},"labels":{"istio-injection":"enabled","serving.knative.dev/release":"v0...
Status:       Active

In our case, we are running v0.10.0 of Knative.

Install using a values.yaml file

If you would like to define the settings with a file, create a values.yaml file with the following overrides:

gateway:
  enabled: false
settings:
  integrations:
    knative:
      enabled: true
      version: {{ . }}  # put installed knative version here!

For our example, we would Replace the {{ . }} with v0.10.0.

Save the file and then run the following commands to install the Gloo Edge components.

helm install gloo gloo/gloo --namespace gloo-system --create-namespace -f values.yaml

Gloo Edge can be installed to a namespace of your choosing with the --namespace flag.

Install using in-line settings

Instead of creating a values.yaml file, you can simply define the settings in-line. This is useful for a small number of values, but quickly becomes impractical if you want to override several values.

Run the following commands to install the Gloo Edge components with version v0.10.0 of Knative.

helm install gloo gloo/gloo --namespace gloo-system --create-namespace \
  --set gateway.enabled=false,settings.integrations.knative.enabled=true,settings.integrations.knative.version=v0.10.0

Verify your Installation

Check that the Gloo Edge pods and services have been created. Depending on your install options, you may see some differences from the following example. And if you choose to install Gloo Edge into a different namespace than the default gloo-system, then you will need to query your chosen namespace instead.

kubectl get all -n gloo-system

NAME                                          READY   STATUS    RESTARTS   AGE
pod/discovery-7b6684f57d-ldcvx                1/1     Running   0          73m
pod/gloo-6658f49f64-9zlgh                     1/1     Running   5          73m
pod/ingress-5476d956c7-rrr6m                  1/1     Running   0          73m
pod/knative-external-proxy-fdfc894fb-6w4m9    1/1     Running   0          73m
pod/knative-internal-proxy-745c9f6f86-t7h5j   1/1     Running   0          73m

NAME                             TYPE           CLUSTER-IP     EXTERNAL-IP     PORT(S)                      AGE
service/gloo                     ClusterIP      10.7.246.232   <none>          9977/TCP                     73m
service/knative-external-proxy   LoadBalancer   10.7.247.23    35.188.41.169   80:30388/TCP,443:32060/TCP   73m
service/knative-internal-proxy   ClusterIP      10.7.243.248   <none>          80/TCP,443/TCP               73m

NAME                                     READY   UP-TO-DATE   AVAILABLE   AGE
deployment.apps/discovery                1/1     1            1           73m
deployment.apps/gloo                     1/1     1            1           73m
deployment.apps/ingress                  1/1     1            1           73m
deployment.apps/knative-external-proxy   1/1     1            1           73m
deployment.apps/knative-internal-proxy   1/1     1            1           73m

NAME                                                DESIRED   CURRENT   READY   AGE
replicaset.apps/discovery-7b6684f57d                1         1         1       73m
replicaset.apps/gloo-6658f49f64                     1         1         1       73m
replicaset.apps/ingress-5476d956c7                  1         1         1       73m
replicaset.apps/knative-external-proxy-fdfc894fb    1         1         1       73m
replicaset.apps/knative-internal-proxy-745c9f6f86   1         1         1       73m

Uninstall

To uninstall Gloo Edge and all related components, simply run the following.

glooctl uninstall

If you installed Gloo Edge to a different namespace, you will have to specify that namespace using the -n option:

glooctl uninstall -n my-namespace

Next Steps

To begin using Gloo Edge with Knative, check out the Knative Getting Started Guide.