track nic usage.

Author: sivakami

test/integration/swiftv2/longRunningCluster/datapath.go

@@ -115,6 +115,7 @@ type TestScenarios struct {
 	PodImage          string
 	Scenarios         []PodScenario
 	VnetSubnetCache   map[string]VnetSubnetInfo // Cache for vnet/subnet info
+	NodeUsageTracker  map[string]map[string]bool // Tracks which nodes are used per vnet/subnet: "vnet/subnet" -> map[nodeName]bool
 }
 
 // VnetSubnetInfo holds network information for a vnet/subnet combination
@@ -336,16 +337,48 @@ func CreateScenarioResources(scenario PodScenario, testScenarios TestScenarios)
 
 	// Step 5: Select appropriate node based on scenario
 	var targetNode string
+	vnetSubnetKey := fmt.Sprintf("%s/%s", scenario.VnetName, scenario.SubnetName)
+	
+	// Initialize node usage tracker for this vnet/subnet if not exists
+	if testScenarios.NodeUsageTracker == nil {
+		testScenarios.NodeUsageTracker = make(map[string]map[string]bool)
+	}
+	if testScenarios.NodeUsageTracker[vnetSubnetKey] == nil {
+		testScenarios.NodeUsageTracker[vnetSubnetKey] = make(map[string]bool)
+	}
+	
 	if scenario.NodeSelector == "low-nic" {
 		if len(nodeInfo.LowNicNodes) == 0 {
 			return fmt.Errorf("scenario %s: no low-NIC nodes available", scenario.Name)
 		}
-		targetNode = nodeInfo.LowNicNodes[0]
+		// Find first unused node in the pool
+		targetNode = ""
+		for _, node := range nodeInfo.LowNicNodes {
+			if !testScenarios.NodeUsageTracker[vnetSubnetKey][node] {
+				targetNode = node
+				testScenarios.NodeUsageTracker[vnetSubnetKey][node] = true
+				break
+			}
+		}
+		if targetNode == "" {
+			return fmt.Errorf("scenario %s: all low-NIC nodes already used for %s", scenario.Name, vnetSubnetKey)
+		}
 	} else { // "high-nic"
 		if len(nodeInfo.HighNicNodes) == 0 {
 			return fmt.Errorf("scenario %s: no high-NIC nodes available", scenario.Name)
 		}
-		targetNode = nodeInfo.HighNicNodes[0]
+		// Find first unused node in the pool
+		targetNode = ""
+		for _, node := range nodeInfo.HighNicNodes {
+			if !testScenarios.NodeUsageTracker[vnetSubnetKey][node] {
+				targetNode = node
+				testScenarios.NodeUsageTracker[vnetSubnetKey][node] = true
+				break
+			}
+		}
+		if targetNode == "" {
+			return fmt.Errorf("scenario %s: all high-NIC nodes already used for %s", scenario.Name, vnetSubnetKey)
+		}
 	}
 
 	// Step 6: Create pod

test/integration/swiftv2/longRunningCluster/datapath_test.go

@@ -99,11 +99,12 @@ var _ = ginkgo.Describe("Datapath Tests", func() {
 
 		// Initialize test scenarios with cache
 		testScenarios := TestScenarios{
-			ResourceGroup:   rg,
-			BuildID:         buildId,
-			PodImage:        "weibeld/ubuntu-networking",
-			Scenarios:       scenarios,
-			VnetSubnetCache: make(map[string]VnetSubnetInfo),
+			ResourceGroup:    rg,
+			BuildID:          buildId,
+			PodImage:         "weibeld/ubuntu-networking",
+			Scenarios:        scenarios,
+			VnetSubnetCache:  make(map[string]VnetSubnetInfo),
+			NodeUsageTracker: make(map[string]map[string]bool),
 		}
 
 		// Run indefinitely until test is cancelled
@@ -125,6 +126,9 @@ var _ = ginkgo.Describe("Datapath Tests", func() {
 			ginkgo.By("Deleting all test scenarios")
 			err = DeleteAllScenarios(testScenarios)
 			gomega.Expect(err).To(gomega.BeNil(), "Failed to delete test scenarios")
+			
+			// Clear node usage tracker for next iteration
+			testScenarios.NodeUsageTracker = make(map[string]map[string]bool)
 
 			ginkgo.By(fmt.Sprintf("Completed iteration %d at %s", iteration, time.Now().Format(time.RFC3339)))