Rancher Requirements

RKE

high-availability RKE cluster

• Three Linux nodes, typically virtual machines, in an infrastructure provider such as Amazon’s EC2, Google Compute Engine, or vSphere.

These nodes must be in the same region/data center. You may place these servers in separate availability zones.

Rancher server data is stored on etcd database that runs on all three nodes.

• etcd is a distributed reliable key-value store for the most critical data of a distributed system, with a focus: Simple, Secure, Fast & Reliable.

etcd database requires an odd number of nodes so that it can always elect a leader with a majority of the etcd cluster.

general installation requirements for OS, container runtime, hardware, and networking.

Deployment Size	Clusters	Nodes	vCPUs	RAM
Small	Up to 150	Up to 1500	2	8 GB
Medium	Up to 300	Up to 3000	4	16 GB
Large	Up to 500	Up to 5000	8	32 GB
X-Large	Up to 1000	Up to 10,000	16	64 GB
XX-Large	Up to 2000	Up to 20,000	32	128 GB

Contact Rancher for more than 2000 clusters and/or 20,000 nodes.

• A load balancer to direct front-end traffic to the three nodes.

RKE tool will deploy an NGINX Ingress controller.

This controller will listen on ports 80 and 443 of the worker nodes, answering traffic destined for specific hostnames.

• A layer-4 load balancer

Install NGINX, stream module is required.

/etc/nginx/nginx.conf

worker_processes 4;
worker_rlimit_nofile 40000;

events {
    worker_connections 8192;
}

stream {
    upstream rancher_servers_http {
        least_conn;
        server <IP_NODE_1>:80 max_fails=3 fail_timeout=5s;
        server <IP_NODE_2>:80 max_fails=3 fail_timeout=5s;
        server <IP_NODE_3>:80 max_fails=3 fail_timeout=5s;
    }
    server {
        listen 80;
        proxy_pass rancher_servers_http;
    }

    upstream rancher_servers_https {
        least_conn;
        server <IP_NODE_1>:443 max_fails=3 fail_timeout=5s;
        server <IP_NODE_2>:443 max_fails=3 fail_timeout=5s;
        server <IP_NODE_3>:443 max_fails=3 fail_timeout=5s;
    }
    server {
        listen     443;
        proxy_pass rancher_servers_https;
    }

}

docker run -d --restart=unless-stopped \
  -p 80:80 -p 443:443 \
  -v /etc/nginx.conf:/etc/nginx/nginx.conf \
  nginx:1.14

• A layer-7 load balancer

• A DNS record to map a URL to the load balancer. This will become the Rancher server URL, and downstream Kubernetes clusters will need to reach it.

RancherD

Deployment Size	Clusters	Nodes	vCPUs	RAM
Small	Up to 5	Up to 50	2	5 GB
Medium	Up to 15	Up to 200	3	9 GB

Worker

Linux

• Install the Required CLI Tools

kubectl - Kubernetes command-line tool.

helm - Package management for Kubernetes.

• Add the Helm Chart Repository

helm repo add rancher-stable https://releases.rancher.com/server-charts/stable

• Create a Namespace for Rancher

kubectl create namespace cattle-system

• Choose your SSL Configuration

Configuraton	Helm Chart Option	Requires cert-manager
Rancher Generated Certificates (Default)	ingress.tls.source=rancher	yes
Let’s Encrypt	ingress.tls.source=letsEncrypt	yes
Certificates from Files	ingress.tls.source=secret	no

• Install cert-manager (if requires)

# Install the CustomResourceDefinition resources separately
kubectl apply --validate=false -f https://github.com/jetstack/cert-manager/releases/download/v1.0.4/cert-manager.crds.yaml

# **Important:**
# If you are running Kubernetes v1.15 or below, you
# will need to add the `--validate=false` flag to your
# kubectl apply command, 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.

# Create the namespace for cert-manager
kubectl create namespace cert-manager

# Add the Jetstack Helm repository
helm repo add jetstack https://charts.jetstack.io

# Update your local Helm chart repository cache
helm repo update

# Install the cert-manager Helm chart
helm install \
  cert-manager jetstack/cert-manager \
  --namespace cert-manager \
  --version v1.0.4

kubectl get pods --namespace cert-manager

NAME                                       READY   STATUS    RESTARTS   AGE
cert-manager-5c6866597-zw7kh               1/1     Running   0          2m
cert-manager-cainjector-577f6d9fd7-tr77l   1/1     Running   0          2m
cert-manager-webhook-787858fcdb-nlzsq      1/1     Running   0          2m