How to Install NGINX ingress controller with Helm

We saw in many posts of this blog, where we were installing a K8s cluster, how to install an NGINX ingress controller with just one command:

kubectl apply -f https://raw.githubusercontent.com/kubernetes/ingress-nginx/controller-v1.1.0/deploy/static/provider/cloud/deploy.yaml

In this post, we will see another way to install NGINX. But, before that, why would we install it differently if we just run one command with the previous method?

Why using Helm

The way we’ve been installing NGINX in all of our K8s installations was deploying NGINX with a default configuration. However, in many situations, we will need to customize this installation and modify values in the manifests of the different K8s resources that get created during the NGINX deployment.

Some examples:

We might need to change the number of replicas to run the controller
We might need to use an existing Load Balancer instead of creating a new one in our cloud provider
We might need to adjust the Resource Limits and set different values for CPU and memory requests/limits
We might need to add custom annotations to enable specific features of NGINX (like sticky sessions, custom headers or SSL/TLS configuration) or specific features of the cloud provider
As we’ll see in a different post, we might need to use more than one ingress controller to segregate internal and external traffic

Making changes for these scenarios will require us manually modifying the yaml files of the NGINX deployment. And this is when Helm becomes a very handy tool.
Helm allows us to use the NGINX chart and make these changes in the values.yaml file as opposed to modifying directly the manifest files.

The values.yaml file is the way Helm parametrizes the installation of all resources, externalizing the values we want to modify to a yaml file, which allows us to control much more the changes to be applied. It will also help us to set a version control and be able know what changes we applied on each update and revert back to a previous deploy if necessary.

Now that we know why, let’s see how to install NGINX with Helm. These are the steps to follow

Install K3s without Traefik

The first thing we need is a K8s cluster. Since we just need to test NGINX we don’t need a full EKS, AKS or OpenShift. We can just use a quick and simple K3s cluster. For that we will install a K3s without Traefik. As we saw in this post, we just need to run this command:

curl -sfL https://get.k3s.io | K3S_KUBECONFIG_MODE="644" INSTALL_K3S_VERSION=<VERSION> INSTALL_K3S_EXEC="--disable traefik" sh -s -

Verify the cluster is running with kubectl get nodes

And lastly, verify that traefik has not been installed with kubectl get pods -n kube-system. You should not see any pod related to traefik in the kube-system namespace.

Install Helm

Follow the steps:

add the gpg key of helm to our repositories

curl https://baltocdn.com/helm/signing.asc | gpg --dearmor | sudo tee /usr/share/keyrings/helm.gpg > /dev/null

Install the additional components required by Helm

sudo apt-get install apt-transport-https

Install Helm

echo "deb [arch=$(dpkg --print-architecture) signed-by=/usr/share/keyrings/helm.gpg] https://baltocdn.com/helm/stable/debian/ all main" | sudo tee /etc/apt/sources.list.d/helm-stable-debian.list
sudo apt-get update
sudo apt-get install helm

Verify installation

helm version

Set up the KUBECONFIG variable so that Helm can connect to the K3s cluster

export KUBECONFIG=/etc/rancher/k3s/k3s.yaml

NGINX Basic Installation with Helm

Add the nginx repository to helm

helm repo add ingress-nginx https://kubernetes.github.io/ingress-nginx

Verify that the new repo is in the list of repos of your Helm installation

helm repo list

update the new repo

helm repo update

We’ll create a dedicated namespace for all the ingress resources called ingress-nginx

kubectl create ns ingress-nginx

And finally, we’ll run the helm command to install the NGINX

helm install ingress-nginx ingress-nginx/ingress-nginx \
--namespace ingress-nginx \
--set controller.ingressClassResourcename=nignx

The Controller can be configured to publish the IP address on each Ingress by setting the controller.publishService.enabled parameter to true during helm install. It is recommended to enable this setting to support applications that may depend on the IP address of the Load Balancer.

Verify NGINX is running

kubectl get all -n ingress-nginx

This will automatically create a Load Balancer. Wait until the <pending> state of the EXTERNAL-IP column changes to the IP address. Verify that with

kubectl get svc -n ingress-nginx

Customizing the Installation

Now that we know how to install NGINX with Helm we'll see in the next post some examples of customizing the installation using Helm commands and the values.yaml file.