Add support for multicast communication with UML/QEMU/KVM.

[tinc] / doc / tinc.conf.5.in

diff --git a/doc/tinc.conf.5.in b/doc/tinc.conf.5.in
index a6ae4f5..d5757c8 100644 (file)
--- a/doc/tinc.conf.5.in
+++ b/doc/tinc.conf.5.in
@@ -129,7 +129,7 @@ If
 is selected, then depending on the operating system both IPv4 and IPv6 or just
 IPv6 listening sockets will be created.
 
-.It Va BindToAddress Li = Ar address Bq experimental
+.It Va BindToAddress Li = Ar address Oo Ar port Oc Bq experimental
 If your computer has more than one IPv4 or IPv6 address,
 .Nm tinc
 will by default listen on all of them for incoming connections.
@@ -137,7 +137,16 @@ Multiple
 .Va BindToAddress
 variables may be specified,
 in which case listening sockets for each specified address are made.
-
+.Pp
+If no
+.Ar port
+is specified, the socket will be bound to the port specified by the
+.Va Port
+option, or to port 655 if neither is given.
+To only bind to a specific port but not to a specific address, use
+.Li *
+for the
+.Ar address .
 .Pp
 This option may not work on all platforms.
 
@@ -210,6 +219,16 @@ All packets are read from this interface.
 Packets received for the local node are written to the raw socket.
 However, at least on Linux, the operating system does not process IP packets destined for the local host.
 
+.It multicast
+Open a multicast UDP socket and bind it to the address and port (separated by spaces) and optionally a TTL value specified using
+.Va Device .
+Packets are read from and written to this multicast socket.
+This can be used to connect to UML, QEMU or KVM instances listening on the same multicast address.
+Do NOT connect multiple
+.Nm tinc 
+daemons to the same multicast address, this will very likely cause routing loops.
+Also note that this can cause decrypted VPN packets to be sent out on a real network if misconfigured.
+
 .It uml Pq not compiled in by default
 Create a UNIX socket with the filename specified by
 .Va Device ,
@@ -452,7 +471,7 @@ Since host configuration files only contain public keys,
 no secrets are revealed by sending out this information.
 .Bl -tag -width indent
 
-.It Va Address Li = Ar address Oo port Oc Bq recommended
+.It Va Address Li = Ar address Oo Ar port Oc Bq recommended
 The IP address or hostname of this tinc daemon on the real network.
 This will only be used when trying to make an outgoing connection to this tinc daemon.
 Optionally, a port can be specified to use for this address.