diff --git a/gns3server/modules/qemu/qemu_vm.py b/gns3server/modules/qemu/qemu_vm.py
index d0305ccc..2006a285 100644
--- a/gns3server/modules/qemu/qemu_vm.py
+++ b/gns3server/modules/qemu/qemu_vm.py
@@ -28,6 +28,7 @@ import subprocess
 import shlex
 import asyncio
 import socket
+import random
 import gns3server
 
 from gns3server.utils import parse_version
@@ -493,9 +494,9 @@ class QemuVM(BaseVM):
         """
 
         if not mac_address:
-            self._mac_address = "00:00:ab:%s:%s:00" % (self.id[-4:-2], self.id[-2:])
+            self._mac_address = "12:34:%02x:%02x:%02x:00" % (random.randint(0, 255), random.randint(0, 255), random.randint(0, 255))
         else:
-            self._mac_address = mac_address
+            self._mac_address = mac_address[:8] + ":%02x:%02x:00" % (random.randint(0, 255), random.randint(0, 255))
 
         log.info('QEMU VM "{name}" [{id}]: MAC address changed to {mac_addr}'.format(name=self._name,
                                                                                      id=self._id,
diff --git a/gns3server/utils/__init__.py b/gns3server/utils/__init__.py
index 9f8ea4a7..06b56d0d 100644
--- a/gns3server/utils/__init__.py
+++ b/gns3server/utils/__init__.py
@@ -30,19 +30,20 @@ def force_unix_path(path):
     return posixpath.normpath(path)
 
 
-def macaddress_to_int(macaddress):
+def macaddress_to_int(mac_address):
     """
     Convert a macaddress with the format 00:0c:29:11:b0:0a to a int
 
-    :param macaddress: The mac address
+    :param mac_address: The mac address
+
     :returns: Integer
     """
-    return int(macaddress.replace(":", ""), 16)
+    return int(mac_address.replace(":", ""), 16)
 
 
 def int_to_macaddress(integer):
     """
-    Convert an integer to a macaddress
+    Convert an integer to a mac address
     """
     return ":".join(textwrap.wrap("%012x" % (integer), width=2))