4. Install Rancher

This section is about how to deploy Rancher for your air gapped environment in a high-availability Kubernetes installation. An air gapped environment could be where Rancher server will be installed offline, behind a firewall, or behind a proxy.

Privileged Access for Rancher

When the Rancher server is deployed in the Docker container, a local Kubernetes cluster is installed within the container for Rancher to use. Because many features of Rancher run as deployments, and privileged mode is required to run containers within containers, you will need to install Rancher with the --privileged option.

Docker Instructions

If you want to continue the air gapped installation using Docker commands, skip the rest of this page and follow the instructions on this page.

Kubernetes Instructions

Rancher recommends installing Rancher on a Kubernetes cluster. A highly available Kubernetes install is comprised of three nodes running the Rancher server components on a Kubernetes cluster. The persistence layer (etcd) is also replicated on these three nodes, providing redundancy and data duplication in case one of the nodes fails.

This section describes installing Rancher:

• 1. Add the Helm Chart Repository
• 2. Choose your SSL Configuration
• 3. Render the Rancher Helm Template
• 4. Install Rancher

1. Add the Helm Chart Repository

From a system that has access to the internet, fetch the latest Helm chart and copy the resulting manifests to a system that has access to the Rancher server cluster.

1. If you haven’t already, install helm locally on a workstation that has internet access. Note: Refer to the Helm version requirements to choose a version of Helm to install Rancher.

2. Use helm repo add command to add the Helm chart repository that contains charts to install Rancher. For more information about the repository choices and which is best for your use case, see Choosing a Version of Rancher.

   Latest: Recommended for trying out the newest features

   Stable: Recommended for production environments

   Alpha: Experimental preview of upcoming releases.
   Note: Upgrades are not supported to, from, or between Alphas.

   helm repo add rancher-<CHART_REPO> https://releases.rancher.com/server-charts/<CHART_REPO>

3. Fetch the latest Rancher chart. This will pull down the chart and save it in the current directory as a .tgz file.

   helm fetch rancher-<CHART_REPO>/rancher

   If you require a specific version of Rancher, you can fetch this with the Helm --version parameter like in the following example:

   helm fetch rancher-stable/rancher --version=v2.4.8

2. Choose your SSL Configuration

Rancher Server is designed to be secure by default and requires SSL/TLS configuration.

When Rancher is installed on an air gapped Kubernetes cluster, there are two recommended options for the source of the certificate.

Note: If you want terminate SSL/TLS externally, see TLS termination on an External Load Balancer.

Helm Chart Options for Air Gap Installations

When setting up the Rancher Helm template, there are several options in the Helm chart that are designed specifically for air gap installations.

3. Render the Rancher Helm Template

Based on the choice your made in 2. Choose your SSL Configuration, complete one of the procedures below.

Option A: Default Self-Signed Certificate

By default, Rancher generates a CA and uses cert-manager to issue the certificate for access to the Rancher server interface.

Note: Recent changes to cert-manager require an upgrade. If you are upgrading Rancher and using a version of cert-manager older than v0.11.0, please see our upgrade cert-manager documentation.

1. Add the cert-manager repo

From a system connected to the internet, add the cert-manager repo to Helm:

helm repo add jetstack https://charts.jetstack.io
helm repo update

2. Fetch the cert-manager chart

Fetch the latest cert-manager chart available from the Helm chart repository.

helm fetch jetstack/cert-manager --version v1.5.1

3. Render the cert-manager template

Render the cert-manager template with the options you would like to use to install the chart. Remember to set the image.repository option to pull the image from your private registry. This will create a cert-manager directory with the Kubernetes manifest files.

helm template cert-manager ./cert-manager-v1.5.1.tgz --output-dir . \
    --namespace cert-manager \
    --set image.repository=<REGISTRY.YOURDOMAIN.COM:PORT>/quay.io/jetstack/cert-manager-controller \
    --set webhook.image.repository=<REGISTRY.YOURDOMAIN.COM:PORT>/quay.io/jetstack/cert-manager-webhook \
    --set cainjector.image.repository=<REGISTRY.YOURDOMAIN.COM:PORT>/quay.io/jetstack/cert-manager-cainjector

4. Download the cert-manager CRD

Download the required CRD file for cert-manager:

   curl -L -o cert-manager/cert-manager-crd.yaml https://github.com/jetstack/cert-manager/releases/download/v1.5.1/cert-manager.crds.yaml

5. Render the Rancher template

Render the Rancher template, declaring your chosen options. Use the reference table below to replace each placeholder. Rancher needs to be configured to use the private registry in order to provision any Rancher launched Kubernetes clusters or Rancher tools.

helm template rancher ./rancher-<VERSION>.tgz --output-dir . \
    --no-hooks \ # prevent files for Helm hooks from being generated
    --namespace cattle-system \
    --set hostname=<RANCHER.YOURDOMAIN.COM> \
    --set certmanager.version=<CERTMANAGER_VERSION> \
    --set rancherImage=<REGISTRY.YOURDOMAIN.COM:PORT>/rancher/rancher \
    --set systemDefaultRegistry=<REGISTRY.YOURDOMAIN.COM:PORT> \ # Set a default private registry to be used in Rancher
    --set useBundledSystemChart=true # Use the packaged Rancher system charts

Optional: To install a specific Rancher version, set the rancherImageTag value, example: --set rancherImageTag=v2.5.8

Option B: Certificates From Files using Kubernetes Secrets

1. Create secrets

Create Kubernetes secrets from your own certificates for Rancher to use. The common name for the cert will need to match the hostname option in the command below, or the ingress controller will fail to provision the site for Rancher.

2. Render the Rancher template

Render the Rancher template, declaring your chosen options. Use the reference table below to replace each placeholder. Rancher needs to be configured to use the private registry in order to provision any Rancher launched Kubernetes clusters or Rancher tools.

   helm template rancher ./rancher-<VERSION>.tgz --output-dir . \
    --no-hooks \ # prevent files for Helm hooks from being generated
    --namespace cattle-system \
    --set hostname=<RANCHER.YOURDOMAIN.COM> \
    --set rancherImage=<REGISTRY.YOURDOMAIN.COM:PORT>/rancher/rancher \
    --set ingress.tls.source=secret \
    --set systemDefaultRegistry=<REGISTRY.YOURDOMAIN.COM:PORT> \ # Set a default private registry to be used in Rancher
    --set useBundledSystemChart=true # Use the packaged Rancher system charts

If you are using a Private CA signed cert, add --set privateCA=true following --set ingress.tls.source=secret:

   helm template rancher ./rancher-<VERSION>.tgz --output-dir . \
    --no-hooks \ # prevent files for Helm hooks from being generated
    --namespace cattle-system \
    --set hostname=<RANCHER.YOURDOMAIN.COM> \
    --set rancherImage=<REGISTRY.YOURDOMAIN.COM:PORT>/rancher/rancher \
    --set ingress.tls.source=secret \
    --set privateCA=true \
    --set systemDefaultRegistry=<REGISTRY.YOURDOMAIN.COM:PORT> \ # Set a default private registry to be used in Rancher
    --set useBundledSystemChart=true # Use the packaged Rancher system charts

Optional: To install a specific Rancher version, set the rancherImageTag value, example: --set rancherImageTag=v2.3.6

Then refer to Adding TLS Secrets to publish the certificate files so Rancher and the ingress controller can use them.

4. Install Rancher

Copy the rendered manifest directories to a system that has access to the Rancher server cluster to complete installation.

Use kubectl to create namespaces and apply the rendered manifests.

If you choose to use self-signed certificates in B. Choose your SSL Configuration, install cert-manager.

For Self-Signed Certificate Installs, Install Cert-manager

Click to expand

If you are using self-signed certificates, install cert-manager:

1. Create the namespace for cert-manager.

   kubectl create namespace cert-manager

2. Create the cert-manager CustomResourceDefinitions (CRDs).

   kubectl apply -f cert-manager/cert-manager-crd.yaml

   Note: If you are running Kubernetes v1.15 or below, you will need to add the --validate=false flag to your kubectl apply command above, or else you will receive a validation error relating to the x-kubernetes-preserve-unknown-fields field in cert-manager’s CustomResourceDefinition resources. This is a benign error and occurs due to the way kubectl performs resource validation.

3. Launch cert-manager.

   kubectl apply -R -f ./cert-manager

Install Rancher with kubectl

kubectl create namespace cattle-system
kubectl -n cattle-system apply -R -f ./rancher

The installation is complete.

Note: If you don’t intend to send telemetry data, opt out telemetry during the initial login. Leaving this active in an air-gapped environment can cause issues if the sockets cannot be opened successfully.

Additional Resources

These resources could be helpful when installing Rancher:

• Rancher Helm chart options
• Adding TLS secrets
• Troubleshooting Rancher Kubernetes Installations