This is taken from B.A.T.M.A.N's website:
https://downloads.open-mesh.org/svn/batman/trunk/batman/INSTALL
===============================================================

  ( This documentation is actually for the stable batman-0.2.x branch. 
  However, the main steps described here for compilation and usage should 
  be almost the same for the currently unstable 0.3.x branch. 
  There is also a very nice HOWTO from Wesley available as a pdf at:
  https://downloads.open-mesh.org/batman/misc/batmand_howto.pdf )

Usage
=====

Make sure you have no firewall running that is blocking UDP 
port 1966 (originator messages), port 1967 (HNA messages). 
Port 1968 has to be open for incoming UDP traffic if you run the
B.A.T.M.A.N. visualization server.

First the network interfaces supposed to participate
in the batman mesh must be configured properly. Assuming you 
are already running olsr on interface eth1 with the IP address 
104.1.12.123/8 and now want to run batman in parallel to olsr 
on the same physical interface but with a 105.1.12.123/8 IP/netmask.

 $ ifconfig eth1:bat 105.1.12.123 netmask 255.0.0.0 broadcast 105.255.255.255
 $ batmand -d 3 eth1:bat
 
This will configure an alias interface on top of eth1 named eth1:bat and start
the batman daemon with debug level 3 on that alias interface. As soon as
another running batmand (with the same netmask and broadcast address) is 
connected to that link (or within the range of the wireless link) 
both batman daemons should see each other and indicate this in the debug output.

The daemon started with debug level 3 can be terminated with ctrl-c.
If no debuglevel is given at startup, using
 
$ batmand eth1:bat

the daemon will immediateley fork to the background (as is the usual behavior 
of a daemon). However you can always connect to the main daemon (running 
in background) by launching a client-batmand process with the 
-c and -d <number> option, where the number represents the desired 
debug-level. The following command will connect to a running batmand 
process providing debug-level 1 information.
 
$ batmand -c -d 1 # shows a list of other nodes in the mesh

$ batmand -c -d 2 # shows a list of nodes offering internet GW access

$ route -n # shows your current routing table as modified by batmand

For a full list of supported debug-levels and other startup options see

 $ batmand -h # providing a brief summary of options and

 $ batmand -H # for a more detailed list of options

Use ctrl-c to terminate a process running in foreground and 
 
$ killall batmand

to terminate the main batmand daemon running in background.

If you want to use one of the batman-internet gateways showed with 
debug-level 2 launch the main batmand using:

 $ batmand -r 3 eth1:bat # to automatically select a reasonable GW
 
 $ batmand -r 3 -p <ip-of-batmand-gw-node> eth1:bat # to set a preferred GW

In case of success this will setup a tunnel to a (preferred) batman-gw-node 
and configure the routing table that all packets matching the default route 
are forwarded (tunneled) respectively.
More information is available using the -h and -H options.




Happy routing!

The B.A.T.M.A.N. contributors

===================================================================

 -- Wesley Tsai <wesleyboy42@gmail.com>  Fri,  7 Sep 2007 20:04:44 +0800
