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Based on kernel version 3.9. Page generated on 2013-05-02 23:10 EST.

1	BATMAN-ADV
2	----------
3	
4	Batman  advanced  is  a new approach to wireless networking which
5	does no longer operate on the IP basis. Unlike the batman daemon,
6	which  exchanges  information  using UDP packets and sets routing
7	tables, batman-advanced operates on ISO/OSI Layer 2 only and uses
8	and  routes  (or  better: bridges) Ethernet Frames. It emulates a
9	virtual network switch of all nodes participating.  Therefore all
10	nodes  appear  to be link local, thus all higher operating proto-
11	cols won't be affected by any changes within the network. You can
12	run almost any protocol above batman advanced, prominent examples
13	are: IPv4, IPv6, DHCP, IPX.
14	
15	Batman advanced was implemented as a Linux kernel driver  to  re-
16	duce the overhead to a minimum. It does not depend on any (other)
17	network driver, and can be used on wifi as well as ethernet  lan,
18	vpn,  etc ... (anything with ethernet-style layer 2).
19	
20	
21	CONFIGURATION
22	-------------
23	
24	Load the batman-adv module into your kernel:
25	
26	# insmod batman-adv.ko
27	
28	The  module  is now waiting for activation. You must add some in-
29	terfaces on which batman can operate. After  loading  the  module
30	batman  advanced  will scan your systems interfaces to search for
31	compatible interfaces. Once found, it will create  subfolders  in
32	the /sys directories of each supported interface, e.g.
33	
34	# ls /sys/class/net/eth0/batman_adv/
35	# iface_status  mesh_iface
36	
37	If an interface does not have the "batman_adv" subfolder it prob-
38	ably is not supported. Not supported  interfaces  are:  loopback,
39	non-ethernet and batman's own interfaces.
40	
41	Note:  After the module was loaded it will continuously watch for
42	new interfaces to verify the compatibility. There is no  need  to
43	reload the module if you plug your USB wifi adapter into your ma-
44	chine after batman advanced was initially loaded.
45	
46	To activate a  given  interface  simply  write  "bat0"  into  its
47	"mesh_iface" file inside the batman_adv subfolder:
48	
49	# echo bat0 > /sys/class/net/eth0/batman_adv/mesh_iface
50	
51	Repeat  this step for all interfaces you wish to add.  Now batman
52	starts using/broadcasting on this/these interface(s).
53	
54	By reading the "iface_status" file you can check its status:
55	
56	# cat /sys/class/net/eth0/batman_adv/iface_status
57	# active
58	
59	To deactivate an interface you have  to  write  "none"  into  its
60	"mesh_iface" file:
61	
62	# echo none > /sys/class/net/eth0/batman_adv/mesh_iface
63	
64	
65	All  mesh  wide  settings  can be found in batman's own interface
66	folder:
67	
68	# ls /sys/class/net/bat0/mesh/
69	# aggregated_ogms        gw_bandwidth           log_level
70	# ap_isolation           gw_mode                orig_interval
71	# bonding                gw_sel_class           routing_algo
72	# bridge_loop_avoidance  hop_penalty            vis_mode
73	# fragmentation
74	
75	
76	There is a special folder for debugging information:
77	
78	# ls /sys/kernel/debug/batman_adv/bat0/
79	# bla_backbone_table  log                 transtable_global
80	# bla_claim_table     originators         transtable_local
81	# gateways            socket              vis_data
82	
83	Some of the files contain all sort of status information  regard-
84	ing  the  mesh  network.  For  example, you can view the table of
85	originators (mesh participants) with:
86	
87	# cat /sys/kernel/debug/batman_adv/bat0/originators
88	
89	Other files allow to change batman's behaviour to better fit your
90	requirements.  For instance, you can check the current originator
91	interval (value in milliseconds which determines how often batman
92	sends its broadcast packets):
93	
94	# cat /sys/class/net/bat0/mesh/orig_interval
95	# 1000
96	
97	and also change its value:
98	
99	# echo 3000 > /sys/class/net/bat0/mesh/orig_interval
100	
101	In very mobile scenarios, you might want to adjust the originator
102	interval to a lower value. This will make the mesh  more  respon-
103	sive to topology changes, but will also increase the overhead.
104	
105	
106	USAGE
107	-----
108	
109	To  make use of your newly created mesh, batman advanced provides
110	a new interface "bat0" which you should use from this  point  on.
111	All  interfaces  added  to  batman  advanced are not relevant any
112	longer because batman handles them for you. Basically, one "hands
113	over" the data by using the batman interface and batman will make
114	sure it reaches its destination.
115	
116	The "bat0" interface can be used like any  other  regular  inter-
117	face.  It needs an IP address which can be either statically con-
118	figured or dynamically (by using DHCP or similar services):
119	
120	# NodeA: ifconfig bat0 192.168.0.1
121	# NodeB: ifconfig bat0 192.168.0.2
122	# NodeB: ping 192.168.0.1
123	
124	Note:  In  order to avoid problems remove all IP addresses previ-
125	ously assigned to interfaces now used by batman advanced, e.g.
126	
127	# ifconfig eth0 0.0.0.0
128	
129	
130	VISUALIZATION
131	-------------
132	
133	If you want topology visualization, at least one mesh  node  must
134	be configured as VIS-server:
135	
136	# echo "server" > /sys/class/net/bat0/mesh/vis_mode
137	
138	Each  node  is  either configured as "server" or as "client" (de-
139	fault: "client").  Clients send their topology data to the server
140	next to them, and server synchronize with other servers. If there
141	is no server configured (default) within the  mesh,  no  topology
142	information   will  be  transmitted.  With  these  "synchronizing
143	servers", there can be 1 or more vis servers sharing the same (or
144	at least very similar) data.
145	
146	When  configured  as  server,  you can get a topology snapshot of
147	your mesh:
148	
149	# cat /sys/kernel/debug/batman_adv/bat0/vis_data
150	
151	This raw output is intended to be easily parsable and convertable
152	with  other tools. Have a look at the batctl README if you want a
153	vis output in dot or json format for instance and how those  out-
154	puts could then be visualised in an image.
155	
156	The raw format consists of comma separated values per entry where
157	each entry is giving information about a  certain  source  inter-
158	face.  Each  entry can/has to have the following values:
159	-> "mac" - mac address of an originator's source interface
160	           (each line begins with it)
161	-> "TQ mac  value"  -  src mac's link quality towards mac address
162	                       of a neighbor originator's interface which
163	                       is being used for routing
164	-> "TT mac" - TT announced by source mac
165	-> "PRIMARY" - this  is a primary interface
166	-> "SEC mac" - secondary mac address of source
167	               (requires preceding PRIMARY)
168	
169	The TQ value has a range from 4 to 255 with 255 being  the  best.
170	The TT entries are showing which hosts are connected to the mesh
171	via bat0 or being bridged into the mesh network.  The PRIMARY/SEC
172	values are only applied on primary interfaces
173	
174	
175	LOGGING/DEBUGGING
176	-----------------
177	
178	All error messages, warnings and information messages are sent to
179	the kernel log. Depending on your operating  system  distribution
180	this  can  be read in one of a number of ways. Try using the com-
181	mands: dmesg, logread, or looking in the files  /var/log/kern.log
182	or  /var/log/syslog.  All  batman-adv  messages are prefixed with
183	"batman-adv:" So to see just these messages try
184	
185	# dmesg | grep batman-adv
186	
187	When investigating problems with your mesh network  it  is  some-
188	times  necessary  to see more detail debug messages. This must be
189	enabled when compiling the batman-adv module. When building  bat-
190	man-adv  as  part of kernel, use "make menuconfig" and enable the
191	option "B.A.T.M.A.N. debugging".
192	
193	Those additional  debug messages can be accessed  using a special
194	file in debugfs
195	
196	# cat /sys/kernel/debug/batman_adv/bat0/log
197	
198	The additional debug output is by default disabled. It can be en-
199	abled  during run time. Following log_levels are defined:
200	
201	0 - All  debug  output  disabled
202	1 - Enable messages related to routing / flooding / broadcasting
203	2 - Enable messages related to route added / changed / deleted
204	4 - Enable messages related to translation table operations
205	8 - Enable messages related to bridge loop avoidance
206	16 - Enable messaged related to DAT, ARP snooping and parsing
207	31 - Enable all messages
208	
209	The debug output can be changed at runtime  using  the  file
210	/sys/class/net/bat0/mesh/log_level. e.g.
211	
212	# echo 6 > /sys/class/net/bat0/mesh/log_level
213	
214	will enable debug messages for when routes change.
215	
216	Counters for different types of packets entering and leaving the
217	batman-adv module are available through ethtool:
218	
219	# ethtool --statistics bat0
220	
221	
222	BATCTL
223	------
224	
225	As batman advanced operates on layer 2 all hosts participating in
226	the  virtual switch are completely transparent for all  protocols
227	above layer 2. Therefore the common diagnosis tools do  not  work
228	as  expected.  To  overcome these problems batctl was created. At
229	the  moment the  batctl contains ping,  traceroute,  tcpdump  and
230	interfaces to the kernel module settings.
231	
232	For more information, please see the manpage (man batctl).
233	
234	batctl is available on http://www.open-mesh.org/
235	
236	
237	CONTACT
238	-------
239	
240	Please send us comments, experiences, questions, anything :)
241	
242	IRC:            #batman   on   irc.freenode.org
243	Mailing-list:   b.a.t.m.a.n@open-mesh.org (optional  subscription
244	          at https://lists.open-mesh.org/mm/listinfo/b.a.t.m.a.n)
245	
246	You can also contact the Authors:
247	
248	Marek  Lindner  <lindner_marek@yahoo.de>
249	Simon  Wunderlich  <siwu@hrz.tu-chemnitz.de>
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