RKE2 Control-plane Deployment

This guide covers prerequisites and steps to install RKE2 for a single node setup of Expertflow CX.

Environment Preparation

For Ubuntu based deployments

1. Disable the firewall

   BASH

   systemctl disable firewalld --now
   systemctl disable apparmor.service
   sudo ufw disable
   reboot

For RHEL

1. Disable the firewall

   BASH

   systemctl disable firewalld --now
   systemctl disable nm-cloud-setup.service nm-cloud-setup.timer
   systemctl disable apparmor.service
   reboot

2. Lock the release to the supported version of RHEL

   BASH

   # The following command set assumes that the supported RHEL version is 8.5
   subscription-manager release --set=8.5; 
   yum clean all;
   subscription-manager release --show;
   rm -rf /var/cache/dnf

3. Update the RHEL packages for supported release

   BASH

   yum update -y

Checklist

RKE2 supported OS list is subject to frequent updates, to verify whether your OS is supported visit this link RKE2 supported OS

• Is Internet access available on the target node? If not available, check RKE2 Air-Gapped install of RKE2 for offline deployment.
• The node is running RKE2 supported OS. RKE2 installation requirements 
• FQDN should be mapped to the underlying node IP.
• NTP should be enabled for all nodes and connected to the same NTP server.
• FirewallD and nm-cloud-setup must be disabled.
• IP Range must not co-exist with already existing IP Range for PODs and Service CIDRs.
• Virtual IP - IP from the same subnet of control plane nodes is needed for VIP failover (required for multi control plane only)
• If your environment restricts external connectivity through an HTTP proxy, follow Configure an HTTP proxy to configure your proxy as per RKE2 recommendations.

Installation Steps

This step is required for the Nginx Ingress controller to allow customized configurations.

Step 1. Create Manifests

1. Create necessary directories for RKE2 deployment

mkdir -p /etc/rancher/rke2/
mkdir -p  /var/lib/rancher/rke2/server/manifests/

1. Generate the ingress-nginx controller config file so that the RKE2 server bootstraps it accordingly.

cat<<EOF| tee /var/lib/rancher/rke2/server/manifests/rke2-ingress-nginx-config.yaml
---
apiVersion: helm.cattle.io/v1
kind: HelmChartConfig
metadata:
  name: rke2-ingress-nginx
  namespace: kube-system
spec:
  valuesContent: |-
    controller:
      metrics:
        service:
          annotations:
            prometheus.io/scrape: "true"
            prometheus.io/port: "10254"
      config:
        use-forwarded-headers: "true"
      allowSnippetAnnotations: "true"
EOF

1. Create deployment manifest called

config.yaml for RKE2 Cluster and replace the IP addresses and corresponding FQDNS according.( add any other fields from the Extra Options sections in config.yaml  at this point ) 

cat<<EOF|tee /etc/rancher/rke2/config.yaml
tls-san:
  - <FQDN>
write-kubeconfig-mode: "0600"
etcd-expose-metrics: true
cni:
  - canal

EOF

In above mentioned template manifest,

• <FQDN> must be pointing towards the first control plane

Step 2. Download the RKE2 binaries and start Installation

Following are some defaults that RKE2 uses while installing RKE2. You may change the following defaults as needed by specifying the switches mentioned.

cluster-cidr and service-cidr are independently evaluated. Decide wisely well before the the cluster deployment. This option is not configurable once the cluster is deployed and workload is running.

1. Run the following command to install RKE2.

curl -sfL https://get.rke2.io |INSTALL_RKE2_TYPE=server  sh - 

1. Enable the rke2-server service

systemctl enable rke2-server.service

1. Start the service

systemctl start rke2-server.service

RKE2 server requires 10-15 minutes (at least) to bootstrap completely  You can check the status of the RKE2 Server using systemctl status rke2-server;  Only procced once everything is up and running or configurational issues might occur requiring redo of all the installation steps.

1. By default, RKE2 deploys all the binaries in

/var/lib/rancher/rke2/bin  path.  Add this path to the system's default PATH for kubectl utility to work appropriately.

export PATH=$PATH:/var/lib/rancher/rke2/bin
export KUBECONFIG=/etc/rancher/rke2/rke2.yaml

1. Also, append these lines into the current user's

.bashrc  file

echo "export PATH=$PATH:/var/lib/rancher/rke2/bin" >> $HOME/.bashrc
echo "export KUBECONFIG=/etc/rancher/rke2/rke2.yaml"  >> $HOME/.bashrc 

1. and source your 

~/.bashrc  

source ~/.bashrc

Step 3. Bash Completion for kubectl

1. Install bash-completion package

yum install bash-completion -y

1. Set-up autocomplete in bash into the current shell,

bash-completion package should be installed first.

source <(kubectl completion bash) 
echo "source <(kubectl completion bash)" >> ~/.bashrc 

1. Also, add alias for short notation of kubectl

echo "alias k=kubectl"  >> ~/.bashrc 
echo "complete -o default -F __start_kubectl k"  >> ~/.bashrc 

1. and source your

~/.bashrc  

source ~/.bashrc

Step 4. Install helm

1. Add this command in ~/.bashrc file.

echo "export KUBECONFIG=/etc/rancher/rke2/rke2.yaml" >> ~/.bashrc

1. run this in the command prompt.

source ~/.bashrc

1. Helm is a super tool to deploy external components. In order to install helm on cluster, execute the following command: 

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

Step 5. Enable bash completion for helm

1. Generate the scripts for help bash completion

helm completion bash > /etc/bash_completion.d/helm

1. Either re-login or run this command to enable the helm bash completion instantly.

source <(helm completion bash)

Next Steps

1. Choose storage - See Storage Solution - Getting Started

2. CX-Core deployment on Kubernetes