fix: Correct nginx-nodeport script to use pod's node IPv6 with externalTrafficPolicy: Local

examples/nginx-nodeport/update-content.sh

@@ -1,28 +1,41 @@
 #!/bin/bash
 
 # Dynamic Mycelium IPv6 Address Discovery Script for NodePort
-# This script fetches Mycelium IPv6 addresses from worker nodes and generates HTML content
+# This script fetches Mycelium IPv6 address of the node where the pod is running
+# With externalTrafficPolicy: Local, service is only accessible on nodes with pods
 
 set -e
 
-echo "🔍 Discovering Mycelium IPv6 addresses from worker nodes..."
+echo "🔍 Discovering Mycelium IPv6 address for pod's node..."
 
-# Fetch IPv6 addresses from cluster worker nodes
-IPV6_ADDRESSES=$(kubectl get nodes -l kubernetes.io/role!=master -o jsonpath='{range .items[*]}{range .status.addresses[?(@.type=="InternalIP")]}{.address}{"\n"}{end}{end}' | grep -E '^[0-9a-f]+:[0-9a-f]+:[0-9a-f]+:[0-9a-f]+:[0-9a-f]+:[0-9a-f]+:[0-9a-f]+:[0-9a-f]+$')
-
-if [ -z "$IPV6_ADDRESSES" ]; then
-    echo "⚠️  No IPv6 addresses found from worker nodes!"
-    echo "Trying all nodes..."
-    IPV6_ADDRESSES=$(kubectl get nodes -o jsonpath='{range .items[*]}{range .status.addresses[?(@.type=="InternalIP")]}{.address}{"\n"}{end}{end}' | grep -E '^[0-9a-f]+:[0-9a-f]+:[0-9a-f]+:[0-9a-f]+:[0-9a-f]+:[0-9a-f]+:[0-9a-f]+:[0-9a-f]+$')
-fi
-
-if [ -z "$IPV6_ADDRESSES" ]; then
-    echo "❌ No IPv6 addresses found!"
+# Get the node where the nginx-nodeport pod is running
+POD_NAME=$(kubectl get pods -l app=nginx-nodeport -o name | head -1)
+if [ -z "$POD_NAME" ]; then
+    echo "❌ No nginx-nodeport pod found!"
+    echo "Please deploy the nginx-nodeport example first:"
+    echo "  kubectl apply -f nginx-nodeport-deployment.yaml"
     exit 1
 fi
 
-echo "✅ Found IPv6 addresses:"
-echo "$IPV6_ADDRESSES"
+POD_NODE=$(kubectl get pods -l app=nginx-nodeport -o jsonpath='{.items[0].spec.nodeName}')
+echo "Pod is running on node: $POD_NODE"
+
+# Get Mycelium IPv6 address of the SPECIFIC node where pod is running
+# This is critical with externalTrafficPolicy: Local
+IPV6_ADDRESS=$(kubectl get node "$POD_NODE" -o jsonpath='{range .status.addresses[?(@.type=="InternalIP")]}{.address}{"\n"}{end}' | grep -E '^[0-9a-f]+:[0-9a-f]+:[0-9a-f]+:[0-9a-f]+:[0-9a-f]+:[0-9a-f]+:[0-9a-f]+:[0-9a-f]+$' | head -1)
+
+if [ -z "$IPV6_ADDRESS" ]; then
+    echo "❌ No IPv6 address found for node $POD_NODE!"
+    exit 1
+fi
+
+IPV6_ADDRESSES="$IPV6_ADDRESS"
+
+echo "✅ Pod's node Mycelium IPv6 address: $IPV6_ADDRESS"
+echo "⚠️  NOTE: With externalTrafficPolicy: Local, service is only accessible on THIS node"
+echo ""
+echo "To access all nodes, scale the deployment:"
+echo "  kubectl scale deployment nginx-nodeport --replicas=3"
 
 # Generate HTML content with dynamic addresses
 cat > /tmp/index.html << 'HTML_EOF'
@@ -180,18 +193,24 @@ cat > /tmp/index.html << 'HTML_EOF'
         </div>
         
         <div class="urls">
-            <h3>🌐 Global Access URLs (NodePort: 30091)</h3>
-            <p><strong>Your website is accessible via these Mycelium worker node IPv6 addresses:</strong></p>
+            <h3>🌐 Access URL (NodePort: 30091)</h3>
+            <p><strong>Your website is accessible via this Mycelium worker node IPv6 address:</strong></p>
             <ul>
 HTML_EOF
 
-# Add each IPv6 address to the HTML
+# Add the single IPv6 address to the HTML
 while IFS= read -r ipv6; do
     echo "                <li><code>http://[$ipv6]:30091</code> ✅</li>" >> /tmp/index.html
+    echo "                <li><strong>Node:</strong> $POD_NODE</li>" >> /tmp/index.html
 done <<< "$IPV6_ADDRESSES"
 
 cat >> /tmp/index.html << 'HTML_EOF'
             </ul>
+            <div style="background: rgba(255, 193, 7, 0.2); padding: 1rem; border-radius: 8px; margin: 1rem 0; border-left: 4px solid #FFC107;">
+                <strong>⚠️ Note:</strong> With <code>externalTrafficPolicy: Local</code>, the service is only accessible on the node where the pod is running.
+            </div>
+            <p><strong>To make accessible on all nodes:</strong></p>
+            <pre style="text-align: left; background: rgba(0,0,0,0.3); padding: 1rem; border-radius: 4px; font-size: 0.8rem;">kubectl scale deployment nginx-nodeport --replicas=3</pre>
             <p><em>Anyone with Mycelium installed can access your website from anywhere!</em></p>
         </div>
         
@@ -219,7 +238,7 @@ cat >> /tmp/index.html << 'HTML_EOF'
 </html>
 HTML_EOF
 
-echo "📝 Generated HTML content with $(echo "$IPV6_ADDRESSES" | wc -l) IPv6 addresses"
+echo "📝 Generated HTML content for pod's node: $POD_NODE"
 
 # Update the ConfigMap
 echo "🔄 Updating ConfigMap..."
@@ -230,10 +249,15 @@ echo ""
 echo "🔄 To apply changes to running pods, restart the deployment:"
 echo "   kubectl rollout restart deployment/nginx-nodeport"
 echo ""
-echo "🌐 Website will be accessible at: http://[worker-node-ipv6]:30091"
+echo "🌐 Website will be accessible at: http://[$IPV6_ADDRESS]:30091"
 echo ""
-echo "📊 Discovered IPv6 addresses:"
-echo "$IPV6_ADDRESSES" | nl
+echo "📊 Pod's node information:"
+echo "  Node: $POD_NODE"
+echo "  Mycelium IPv6: $IPV6_ADDRESS"
+echo ""
+echo "⚠️  Note: Service is only accessible on this specific node"
+echo "   To make accessible on all nodes, scale to 3 replicas:"
+echo "   kubectl scale deployment nginx-nodeport --replicas=3"
 
 # Cleanup
 rm -f /tmp/index.html