diff --git a/memberlist_test.go b/memberlist_test.go
index 75b3534a3..501af4e69 100644
--- a/memberlist_test.go
+++ b/memberlist_test.go
@@ -14,6 +14,7 @@ import (
 	"strconv"
 	"strings"
 	"sync"
+	"sync/atomic"
 	"testing"
 	"time"
 
@@ -23,18 +24,29 @@ import (
 	"github.com/stretchr/testify/require"
 )
 
-var bindLock sync.Mutex
-var bindNum byte = 10
+var bindNum0 uint32 = 9
+var bindNum1 uint32 = 9
+var bindNum2 uint32 = 9
 
-func getBindAddrNet(network byte) net.IP {
-	bindLock.Lock()
-	defer bindLock.Unlock()
+func getBindNum(bindNum *uint32, max uint32) uint32 {
+	atomic.AddUint32(bindNum, 1)
+	if *bindNum > max {
+		atomic.StoreUint32(bindNum, 10)
+	}
+	return *bindNum
+}
 
-	result := net.IPv4(127, 0, network, bindNum)
-	bindNum++
-	if bindNum > 255 {
-		bindNum = 10
+func getBindAddrNet(network byte) net.IP {
+	var bind uint32
+	switch network {
+	case 0:
+		bind = getBindNum(&bindNum0, 255)
+	case 1:
+		bind = getBindNum(&bindNum1, 14)
+	case 2:
+		bind = getBindNum(&bindNum2, 14)
 	}
+	result := net.IPv4(127, 0, network, byte(bind))
 
 	return result
 }
@@ -1586,8 +1598,6 @@ func TestMemberlist_Join_IPv6(t *testing.T) {
 	}
 	// Since this binds to all interfaces we need to exclude other tests
 	// from grabbing an interface.
-	bindLock.Lock()
-	defer bindLock.Unlock()
 
 	c1 := DefaultLANConfig()
 	c1.Name = "A"
diff --git a/test/setup_subnet.sh b/test/setup_subnet.sh
index b6397b207..d74626c55 100755
--- a/test/setup_subnet.sh
+++ b/test/setup_subnet.sh
@@ -29,10 +29,21 @@ case $OSTYPE in
         ;;
 esac
 
-# Setup loopback
-for j in 0 1 2
+# first loopback, use intensively
+for ((i=10;i<256;i++))
+  do
+      if [ "$action" = "up" ]
+      then
+        sudo ifconfig lo0 alias 127.0.0.$i up
+      else
+        sudo ifconfig lo0 127.0.0.$i delete
+     fi
+  done
+
+# Not use much, only need a few
+for j in 1 2
 do
-  for ((i=2;i<256;i++))
+  for ((i=10;i<15;i++))
   do
       if [ "$action" = "up" ]
       then
@@ -42,3 +53,4 @@ do
      fi
   done
 done
+