diff --git a/share/man/man4/tap.4 b/share/man/man4/tap.4
--- a/share/man/man4/tap.4
+++ b/share/man/man4/tap.4
@@ -203,6 +203,21 @@
 The interface name will be returned in the
 .Va ifr_name
 field.
+.It Dv TAPSTRANSIENT
+The argument should be a pointer to an
+.Va int ;
+this sets the transient flag on
+the
+.Nm
+device.
+A transient
+.Nm
+will be destroyed upon last close.
+.It Dv TAPGTRANSIENT
+The argument should be a pointer to an
+.Va int ;
+this stores the current state (enabled or disabled) of the transient flag into
+it.
 .It Dv FIONBIO
 Turn non-blocking I/O for reads off or on, according as the argument
 .Va int Ns 's
diff --git a/share/man/man4/tun.4 b/share/man/man4/tun.4
--- a/share/man/man4/tun.4
+++ b/share/man/man4/tun.4
@@ -282,6 +282,21 @@
 the ioctl sets the value to one if the device is in
 .Dq multi-af
 mode, and zero otherwise.
+.It Dv TUNSTRANSIENT
+The argument should be a pointer to an
+.Va int ;
+this sets the transient flag on
+the
+.Nm
+device.
+A transient
+.Nm
+will be destroyed upon last close.
+.It Dv TUNGTRANSIENT
+The argument should be a pointer to an
+.Va int ;
+this stores the current state (enabled or disabled) of the transient flag into
+it.
 .It Dv FIONBIO
 Turn non-blocking I/O for reads off or on, according as the argument
 .Vt int Ns 's
diff --git a/sys/net/if_clone.h b/sys/net/if_clone.h
--- a/sys/net/if_clone.h
+++ b/sys/net/if_clone.h
@@ -149,7 +149,7 @@
 int	if_clone_list(struct if_clonereq *);
 void	if_clone_restoregroup(struct ifnet *);
 
-/* The below interfaces are used only by epair(4). */
+/* The below interfaces are used only by epair(4) and tun(4)/tap(4). */
 void	if_clone_addif(struct if_clone *, struct ifnet *);
 int	if_clone_destroyif(struct if_clone *, struct ifnet *);
 
diff --git a/sys/net/if_tap.h b/sys/net/if_tap.h
--- a/sys/net/if_tap.h
+++ b/sys/net/if_tap.h
@@ -57,6 +57,8 @@
 #define	TAPGIFNAME		TUNGIFNAME
 #define	TAPSVNETHDR		_IOW('t', 91, int)
 #define	TAPGVNETHDR		_IOR('t', 94, int)
+#define	TAPSTRANSIENT		TUNSTRANSIENT
+#define	TAPGTRANSIENT		TUNGTRANSIENT
 
 /* VMware ioctl's */
 #define VMIO_SIOCSIFFLAGS	_IOWINT('V', 0)
diff --git a/sys/net/if_tun.h b/sys/net/if_tun.h
--- a/sys/net/if_tun.h
+++ b/sys/net/if_tun.h
@@ -43,5 +43,7 @@
 #define	TUNSIFPID	_IO('t', 95)
 #define	TUNSIFHEAD	_IOW('t', 96, int)
 #define	TUNGIFHEAD	_IOR('t', 97, int)
+#define	TUNSTRANSIENT	_IOW('t', 98, int)
+#define	TUNGTRANSIENT	_IOR('t', 99, int)
 
 #endif /* !_NET_IF_TUN_H_ */
diff --git a/sys/net/if_tuntap.c b/sys/net/if_tuntap.c
--- a/sys/net/if_tuntap.c
+++ b/sys/net/if_tuntap.c
@@ -131,6 +131,7 @@
 #define	TUN_DYING	0x0200
 #define	TUN_L2		0x0400
 #define	TUN_VMNET	0x0800
+#define	TUN_TRANSIENT	0x1000
 
 #define	TUN_DRIVER_IDENT_MASK	(TUN_L2 | TUN_VMNET)
 #define	TUN_READY		(TUN_OPEN | TUN_INITED)
@@ -1223,6 +1224,18 @@
 	tun_vnethdr_set(ifp, 0);
 
 	tun_unbusy_locked(tp);
+	if ((tp->tun_flags & TUN_TRANSIENT) != 0) {
+		int error __diagused;
+
+		/* Mark it busy so that nothing can re-open it. */
+		tp->tun_flags |= TUN_DYING;
+		TUN_UNLOCK(tp);
+
+		error = if_clone_destroyif(NULL, ifp);
+		MPASS(error == 0);
+		return;
+	}
+
 	TUN_UNLOCK(tp);
 }
 
@@ -1674,6 +1687,19 @@
 	case TUNGDEBUG:
 		*(int *)data = tundebug;
 		break;
+	case TUNSTRANSIENT:
+		TUN_LOCK(tp);
+		if (*(int *)data)
+			tp->tun_flags |= TUN_TRANSIENT;
+		else
+			tp->tun_flags &= ~TUN_TRANSIENT;
+		TUN_UNLOCK(tp);
+		break;
+	case TUNGTRANSIENT:
+		TUN_LOCK(tp);
+		*(int *)data = (tp->tun_flags & TUN_TRANSIENT) != 0;
+		TUN_UNLOCK(tp);
+		break;
 	case FIONBIO:
 		break;
 	case FIOASYNC: