diff --git a/cmd/harvest/harvest.go b/cmd/harvest/harvest.go
index 7f582f56e..bab546a04 100644
--- a/cmd/harvest/harvest.go
+++ b/cmd/harvest/harvest.go
@@ -504,7 +504,7 @@ func getPollerPrometheusPort(pollerName string, opts *options) int {
 		return opts.promPort
 	}
 
-	if promPort, err = conf.GetPrometheusExporterPorts(pollerName); err != nil {
+	if promPort, err = conf.GetPrometheusExporterPorts(pollerName, false); err != nil {
 		fmt.Println(err)
 		return 0
 	}
diff --git a/cmd/tools/generate/generate.go b/cmd/tools/generate/generate.go
index 1cec382dd..d417be399 100644
--- a/cmd/tools/generate/generate.go
+++ b/cmd/tools/generate/generate.go
@@ -162,10 +162,9 @@ func generateDocker(path string, kind int) {
 	if err != nil {
 		panic(err)
 	}
-	conf.ValidatePortInUse = true
 	var filesd []string
 	for _, v := range conf.Config.PollersOrdered {
-		port, _ := conf.GetPrometheusExporterPorts(v)
+		port, _ := conf.GetPrometheusExporterPorts(v, true)
 		pollerInfo := PollerInfo{
 			ServiceName:   normalizeContainerNames(v),
 			PollerName:    v,
diff --git a/pkg/conf/conf.go b/pkg/conf/conf.go
index c36e97a06..1a262f5b8 100644
--- a/pkg/conf/conf.go
+++ b/pkg/conf/conf.go
@@ -21,7 +21,6 @@ import (
 
 var Config = HarvestConfig{}
 var configRead = false
-var ValidatePortInUse = false
 
 const (
 	DefaultAPIVersion = "1.3"
@@ -32,6 +31,7 @@ const (
 // TestLoadHarvestConfig is used by testing code to reload a new config
 func TestLoadHarvestConfig(configPath string) {
 	configRead = false
+	promPortRangeMapping = make(map[string]PortMap)
 	err := LoadHarvestConfig(configPath)
 	if err != nil {
 		log.Fatalf("Failed to load config at=[%s] err=%+v\n", configPath, err)
@@ -179,12 +179,12 @@ func GetHarvestLogPath() string {
 }
 
 // GetPrometheusExporterPorts returns the Prometheus port for the given poller
-func GetPrometheusExporterPorts(pollerName string) (int, error) {
+func GetPrometheusExporterPorts(pollerName string, validatePortInUse bool) (int, error) {
 	var port int
 	var isPrometheusExporterConfigured bool
 
 	if len(promPortRangeMapping) == 0 {
-		loadPrometheusExporterPortRangeMapping()
+		loadPrometheusExporterPortRangeMapping(validatePortInUse)
 	}
 	poller := Config.Pollers[pollerName]
 	if poller == nil {
@@ -229,18 +229,18 @@ type PortMap struct {
 	freePorts map[int]struct{}
 }
 
-func PortMapFromRange(address string, portRange *IntRange) PortMap {
+func PortMapFromRange(address string, portRange *IntRange, validatePortInUse bool) PortMap {
 	portMap := PortMap{}
 	portMap.freePorts = make(map[int]struct{})
 	start := portRange.Min
 	end := portRange.Max
 	for i := start; i <= end; i++ {
 		portMap.portSet = append(portMap.portSet, i)
-		if ValidatePortInUse {
+		if validatePortInUse {
 			portMap.freePorts[i] = struct{}{}
 		}
 	}
-	if !ValidatePortInUse {
+	if !validatePortInUse {
 		portMap.freePorts = util.CheckFreePorts(address, portMap.portSet)
 	}
 	return portMap
@@ -248,12 +248,12 @@ func PortMapFromRange(address string, portRange *IntRange) PortMap {
 
 var promPortRangeMapping = make(map[string]PortMap)
 
-func loadPrometheusExporterPortRangeMapping() {
+func loadPrometheusExporterPortRangeMapping(validatePortInUse bool) {
 	for k, v := range Config.Exporters {
 		if v.Type == "Prometheus" {
 			if v.PortRange != nil {
 				// we only care about free ports on the localhost
-				promPortRangeMapping[k] = PortMapFromRange("localhost", v.PortRange)
+				promPortRangeMapping[k] = PortMapFromRange("localhost", v.PortRange, validatePortInUse)
 			}
 		}
 	}
diff --git a/pkg/conf/conf_test.go b/pkg/conf/conf_test.go
index c461dc667..a003a1b66 100644
--- a/pkg/conf/conf_test.go
+++ b/pkg/conf/conf_test.go
@@ -12,8 +12,6 @@ var testYml = "../../cmd/tools/doctor/testdata/testConfig.yml"
 
 func TestGetPrometheusExporterPorts(t *testing.T) {
 	TestLoadHarvestConfig(testYml)
-	// Test without checking
-	ValidatePortInUse = true
 	type args struct {
 		pollerNames []string
 	}
@@ -29,7 +27,7 @@ func TestGetPrometheusExporterPorts(t *testing.T) {
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
 			for i, v := range tt.args.pollerNames {
-				got, err := GetPrometheusExporterPorts(v)
+				got, err := GetPrometheusExporterPorts(v, true)
 				if (err != nil) != tt.wantErr[i] {
 					t.Errorf("GetPrometheusExporterPorts() error = %v, wantErr %v", err, tt.wantErr)
 					return
@@ -44,8 +42,8 @@ func TestGetPrometheusExporterPorts(t *testing.T) {
 
 func TestGetPrometheusExporterPortsIssue284(t *testing.T) {
 	TestLoadHarvestConfig("../../cmd/tools/doctor/testdata/issue-284.yml")
-	loadPrometheusExporterPortRangeMapping()
-	got, _ := GetPrometheusExporterPorts("issue-284")
+	loadPrometheusExporterPortRangeMapping(false)
+	got, _ := GetPrometheusExporterPorts("issue-284", false)
 	if got != 0 {
 		t.Fatalf("expected port to be 0 but was %d", got)
 	}