From ff7c781e25150eb0c0f7996a672badb2eba2ea6e Mon Sep 17 00:00:00 2001
From: Adrian Moisey <adrian@changeover.za.net>
Date: Sat, 5 Jul 2025 10:54:10 +0200
Subject: [PATCH] Loop over all IP address from each node

Change the e2e test to test all InternalIPs from each node.

https://github.com/kubernetes/kubernetes/blob/3d6e49e3c24324588c354ff38d5afdb1e27f204f/pkg/proxy/healthcheck/service_health.go#L66
---
 test/e2e/network/loadbalancer.go | 49 +++++++++++++++++++++-----------
 1 file changed, 32 insertions(+), 17 deletions(-)

diff --git a/test/e2e/network/loadbalancer.go b/test/e2e/network/loadbalancer.go
index 9e8b9124c9d..5d9b632b225 100644
--- a/test/e2e/network/loadbalancer.go
+++ b/test/e2e/network/loadbalancer.go
@@ -1103,7 +1103,20 @@ var _ = common.SIGDescribe("LoadBalancers ExternalTrafficPolicy: Local", feature
 			framework.Failf("Service HealthCheck NodePort was not allocated")
 		}
 
-		ips := e2enode.CollectAddresses(nodes, v1.NodeInternalIP)
+		// Collect InternalIP addresses for each node.
+		nodeInternalIPs := make(map[string]sets.Set[string], len(nodes.Items))
+		for i := range nodes.Items {
+			node := &nodes.Items[i]
+			internalIPs := sets.New[string]()
+			for _, addr := range node.Status.Addresses {
+				if addr.Type == v1.NodeInternalIP && addr.Address != "" {
+					internalIPs.Insert(addr.Address)
+				}
+			}
+			if internalIPs.Len() > 0 {
+				nodeInternalIPs[node.Name] = internalIPs
+			}
+		}
 
 		ingressIP := e2eservice.GetIngressPoint(&svc.Status.LoadBalancer.Ingress[0])
 		svcTCPPort := int(svc.Spec.Ports[0].Port)
@@ -1128,22 +1141,24 @@ var _ = common.SIGDescribe("LoadBalancers ExternalTrafficPolicy: Local", feature
 
 			// HealthCheck should pass only on the node where num(endpoints) > 0
 			// All other nodes should fail the healthcheck on the service healthCheckNodePort
-			for n, internalIP := range ips {
-				// Make sure the loadbalancer picked up the health check change.
-				// Confirm traffic can reach backend through LB before checking healthcheck nodeport.
-				e2eservice.TestReachableHTTP(ctx, ingressIP, svcTCPPort, e2eservice.KubeProxyLagTimeout)
-				expectedSuccess := nodes.Items[n].Name == endpointNodeName
-				port := strconv.Itoa(healthCheckNodePort)
-				ipPort := net.JoinHostPort(internalIP, port)
-				framework.Logf("Health checking %s, http://%s/healthz, expectedSuccess %v", nodes.Items[n].Name, ipPort, expectedSuccess)
-				err := testHTTPHealthCheckNodePortFromTestContainer(ctx,
-					config,
-					internalIP,
-					healthCheckNodePort,
-					e2eservice.KubeProxyEndpointLagTimeout,
-					expectedSuccess,
-					threshold)
-				framework.ExpectNoError(err)
+			for n, internalIPs := range nodeInternalIPs {
+				for ip := range internalIPs {
+					// Make sure the loadbalancer picked up the health check change.
+					// Confirm traffic can reach backend through LB before checking healthcheck nodeport.
+					e2eservice.TestReachableHTTP(ctx, ingressIP, svcTCPPort, e2eservice.KubeProxyLagTimeout)
+					expectedSuccess := n == endpointNodeName
+					port := strconv.Itoa(healthCheckNodePort)
+					ipPort := net.JoinHostPort(ip, port)
+					framework.Logf("Health checking %s, http://%s/healthz, expectedSuccess %v", n, ipPort, expectedSuccess)
+					err := testHTTPHealthCheckNodePortFromTestContainer(ctx,
+						config,
+						ip,
+						healthCheckNodePort,
+						e2eservice.KubeProxyEndpointLagTimeout,
+						expectedSuccess,
+						threshold)
+					framework.ExpectNoError(err)
+				}
 			}
 
 			err = f.ClientSet.AppsV1().Deployments(namespace).Delete(ctx, serviceName, metav1.DeleteOptions{})