Deploying Kubernetes cluster with KGateway on AWS for beginners

In this blog, we will quickly go through how can we deploy our application on AWS EKS cluster with kgateway.

We will go through following things -

• Installing Gateway Crd’s

• Deploying a FooBar test application

• Exposing endpoints via KGateway

• Accessing our services externally

If you don’t know how to create an eks cluster this video might help you out -

Install Gateway API CRD’s →

kubectl apply -f https://github.com/kubernetes-sigs/gateway-api/releases/download/v1.3.0/standard-install.yaml

Check if resources have installed →

kubectl api-resources --api-group=gateway.networking.k8s.io

You should get following output →

NAME              SHORTNAMES   APIGROUP                    NAMESPACED   KIND
gatewayclasses    gc           gateway.networking.k8s.io   false        GatewayClass
gateways          gtw          gateway.networking.k8s.io   true         Gateway
grpcroutes                     gateway.networking.k8s.io   true         GRPCRoute
httproutes                     gateway.networking.k8s.io   true         HTTPRoute
referencegrants   refgrant     gateway.networking.k8s.io   true         ReferenceGrant

Install helm →

curl https://raw.githubusercontent.com/helm/helm/main/scripts/get-helm-3 | bash

Deploy the kgateway CRDs by using Helm →

helm upgrade -i --create-namespace --namespace kgateway-system --version v2.0.4 kgateway-crds oci://cr.kgateway.dev/kgateway-dev/charts/kgateway-crds

Install the kgateway CRDs using Helm →

helm upgrade -i --namespace kgateway-system --version v2.0.4 kgateway oci://cr.kgateway.dev/kgateway-dev/charts/kgateway

Now your gateway is up and running. Now to check if is working →

kubectl get pods -n kgateway-system

output →

NAME                       READY   STATUS    RESTARTS   AGE
kgateway-7dcc5fbf9-cdqwh   1/1     Running   0          14s

Now lets deploy our test application.

Below we are setting up our fooBar application, in there we have 2 pods. 1 of foo server that has route /foo and return foo-app and 2nd one is bar server that has route /bar and returns bar-app.

copy paste this in the terminal to spin up pods and services →

cat <<EOF | kubectl apply -f -
kind: Pod
apiVersion: v1
metadata:
  name: foo-app
  labels:
    app: foo
spec:
  containers:
  - command:
    - /agnhost
    - serve-hostname
    - --http=true
    - --port=8080
    image: registry.k8s.io/e2e-test-images/agnhost:2.39
    name: foo-app
---
kind: Service
apiVersion: v1
metadata:
  name: foo-service
spec:
  selector:
    app: foo
  ports:
  - port: 8080
---
kind: Pod
apiVersion: v1
metadata:
  name: bar-app
  labels:
    app: bar
spec:
  containers:
  - command:
    - /agnhost
    - serve-hostname
    - --http=true
    - --port=8080
    image: registry.k8s.io/e2e-test-images/agnhost:2.39
    name: bar-app
---
kind: Service
apiVersion: v1
metadata:
  name: bar-service
spec:
  selector:
    app: bar
  ports:
  - port: 8080
---
EOF

pod/foo-app created
service/foo-service created
pod/bar-app created
service/bar-service created

Now let’s set up our gateway. This will create a gateway with name my-gateway on port 80 →

cat <<EOF | kubectl apply -f -
apiVersion: gateway.networking.k8s.io/v1
kind: Gateway
metadata:
  name: my-gateway
spec:
  gatewayClassName: kgateway
  listeners:
  - name: http
    port: 80
    protocol: HTTP
EOF

But wait we did not specify where should the request to our applications route to. How will it route proper then?

For that we need to set up a httpRouter that will be connected to our gateway and route the requests to appropriate pods.

cat <<EOF | kubectl apply -f -
apiVersion: gateway.networking.k8s.io/v1
kind: HTTPRoute
metadata:
  name: hello
spec:
  parentRefs:
  - name: my-gateway
  # hostnames:
  # - "hello.example.com"
  rules:
  - matches:
    - path:
        type: PathPrefix
        value: /foo
    backendRefs:
    - name: foo-service
      port: 8080
  - matches:
    - path:
        type: PathPrefix
        value: /bar
    backendRefs:
    - name: bar-service
      port: 8080
EOF

Now our application has been completely deployed

kubectl get gateway

this will give us the gateway that we just setup

NAME         CLASS      ADDRESS                                                                   PROGRAMMED   AGE
my-gateway   kgateway   a869d3b6146174ac4aae7a37404f3edf-991812074.ap-south-1.elb.amazonaws.com   True         33s

now as you can see our gateway has been set up and has an address a869d3b6146174ac4aae7a37404f3edf-991812074.ap-south-1.elb.amazonaws.com and we can access our application at this address.

kgatewaybasic % curl a869d3b6146174ac4aae7a37404f3edf-991812074.ap-south-1.elb.amazonaws.com/foo
foo-app                      

kgatewaybasic % curl a869d3b6146174ac4aae7a37404f3edf-991812074.ap-south-1.elb.amazonaws.com/bar
bar-app