diff --git a/src/settings/iptunnelsetting.h b/src/settings/iptunnelsetting.h
--- a/src/settings/iptunnelsetting.h
+++ b/src/settings/iptunnelsetting.h
@@ -24,6 +24,16 @@
 #include <networkmanagerqt/networkmanagerqt_export.h>
 #include "setting.h"
 
+#if !NM_CHECK_VERSION(1, 12, 0)
+#define NM_IP_TUNNEL_FLAG_NONE                            0x0
+#define NM_IP_TUNNEL_FLAG_IP6_IGN_ENCAP_LIMIT             0x1
+#define NM_IP_TUNNEL_FLAG_IP6_USE_ORIG_TCLASS             0x2
+#define NM_IP_TUNNEL_FLAG_IP6_USE_ORIG_FLOWLABEL          0x4
+#define NM_IP_TUNNEL_FLAG_IP6_MIP6_DEV                    0x8
+#define NM_IP_TUNNEL_FLAG_IP6_RCV_DSCP_COPY               0x10
+#define NM_IP_TUNNEL_FLAG_IP6_USE_ORIG_FWMARK             0x20
+#endif
+
 namespace NetworkManager
 {
 
diff --git a/src/settings/iptunnelsetting.cpp b/src/settings/iptunnelsetting.cpp
--- a/src/settings/iptunnelsetting.cpp
+++ b/src/settings/iptunnelsetting.cpp
@@ -32,7 +32,7 @@
     , mode(IpTunnelSetting::Unknown)
     , pathMtuDiscovery(true)
     , encapsulationLimit(0)
-    , flags(IpTunnelSetting::Unknown)
+    , flags(IpTunnelSetting::None)
     , flowLabel(0)
     , mtu(0)
     , tos(0)