RKE2 Cluster v1.32 to v1.33 Upgrade

In this article I will show you how to upgrade the RKE2 Cluster from v1.32 to v1.33 using Rancher. Rancher transforms complex Kubernetes operations into simple point-and-click actions. Instead of manually upgrading each cluster node with SSH and command-line tools, Rancher's web interface lets you orchestrate entire cluster upgrades with just a few clicks from your browser. Keeping RKE2 Cluster current ensures you have the latest features, security patches, and bug fixes.

So, let's get started…

Environment

• RKE2 Cluster and Rancher Manager

RKE2 Cluster Upgrade

1. Make sure domain mapping

# exec on all nodes
cat /etc/hosts
---
172.20.20.65 at-rke2-1 at-rke2-1.at.lab rancher.at.lab
172.20.20.66 at-rke2-2 at-rke2-2.at.lab
172.20.20.67 at-rke2-3 at-rke2-3.at.lab

2. Create sample apps

# exec on master node
export KUBECONFIG=/etc/rancher/rke2/rke2.yaml
kubectl create deployment nginx-upgrade --image=nginx --replicas=2
kubectl expose deployment nginx-upgrade --port=80 --target-port=80 
kubectl create ingress nginx-upgrade --class=nginx --rule="nginx-upgrade.at.lab/*=nginx-upgrade:80"

nano /etc/hosts
---
172.20.20.67 nginx-upgrade.at.lab

3. Create script for monitoring apps

# exec on master node
nano monitoring.sh
---
#!/bin/bash

# List of URLs to check
URLS=(
  "http://nginx-upgrade.at.lab"
)

EXPECTED_STATUS=200  # expected HTTP status
INTERVAL=1           # seconds between checks

echo "📡 Starting Ingress monitoring..."
echo "Expected status: $EXPECTED_STATUS"
echo "Check interval: $INTERVAL seconds"
echo "Press Ctrl+C to stop."

while true; do

    for url in "${URLS[@]}"; do
        STATUS_CODE=$(curl -s -o /dev/null -w "%{http_code}" "$url")

        if [ "$STATUS_CODE" -eq "$EXPECTED_STATUS" ]; then
            echo "✅ $(date '+%Y-%m-%d %H:%M:%S') - $url is OK (HTTP $STATUS_CODE)"
        else
            echo "❌ $(date '+%Y-%m-%d %H:%M:%S') - $url returned HTTP $STATUS_CODE"
        fi
    done

    sleep $INTERVAL
done

chmod +x monitoring.sh

4. Run monitoring script

# exec on master node
./monitoring.sh >> monitoring.log

# other panel/windows
tail -f monitoring.log
kubectl get po -A --watch

5. Upgrade cluster via rancher

upgrade process

upgrade completed

6. Verification

7. Operational test

# exec on master node
nano /etc/hosts
---
172.20.20.65 #rancher.at.lab
172.20.20.67 rancher.at.lab

source ~/.bashrc
kubectx
kubectx rke2-cluster

# exec on master node
kubectl create deployment nginx-aft-upgrade --image=nginx --replicas=1
kubectl expose deployment nginx-aft-upgrade --port=80 --target-port=80 
kubectl create ingress nginx-aft-upgrade --class=nginx --rule="nginx-aft-upgrade.at.lab/*=nginx-aft-upgrade:80"

nano /etc/hosts
---
172.20.20.67 nginx-aft-upgrade.at.lab

Thank You.