Move responsibility for local discovery to UDP discovery.

[tinc] / doc / tinc.texi

diff --git a/doc/tinc.texi b/doc/tinc.texi
index 2cb55a7..dc797fb 100644 (file)
--- a/doc/tinc.texi
+++ b/doc/tinc.texi
@@ -1081,8 +1081,8 @@ This will allow direct communication using LAN addresses, even if both peers are
 and they only ConnectTo a third node outside the NAT,
 which normally would prevent the peers from learning each other's LAN address.
 
-Currently, local discovery is implemented by sending broadcast packets to the LAN during path MTU discovery.
-This feature may not work in all possible situations.
+Currently, local discovery is implemented by sending some packets to the local address of the node during UDP discovery.
+This will not work with old nodes that don't transmit their local address.
 
 @cindex LocalDiscoveryAddress
 @item LocalDiscoveryAddress <@var{address}>
@@ -1232,6 +1232,22 @@ and will only allow connections with nodes for which host config files are prese
 @file{@value{sysconfdir}/tinc/@var{netname}/hosts/} directory.
 Setting this options also implicitly sets StrictSubnets.
 
+@cindex UDPDiscovey
+@item UDPDiscovery = <yes|no> (yes)
+When this option is enabled tinc will try to establish UDP connectivity to nodes,
+using TCP while it determines if a node is reachable over UDP. If it is disabled,
+tinc always assumes a node is reachable over UDP.
+Note that tinc will never use UDP with nodes that have TCPOnly enabled.
+
+@cindex UDPDiscoveryInterval
+@item UDPDiscoveryInterval = <seconds> (9)
+The minimum amount of time between sending UDP ping datagrams to test UDP connectivity.
+
+@cindex UDPDiscoveryTimeout
+@item UDPDiscoveryTimeout = <seconds> (30)
+If tinc doesn't receive any UDP ping replies over the specified interval,
+it will assume UDP communication is broken and will fall back to TCP.
+
 @cindex UDPRcvBuf
 @item UDPRcvBuf = <bytes> (OS default)
 Sets the socket receive buffer size for the UDP socket, in bytes.