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Based on kernel version 3.15.4. Page generated on 2014-07-07 09:03 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        distributed_arp_table  gw_sel_class    orig_interval
70	#ap_isolation           fragmentation          hop_penalty     routing_algo
71	#bonding                gw_bandwidth           isolation_mark  vlan0
72	#bridge_loop_avoidance  gw_mode                log_level
73	
74	There is a special folder for debugging information:
75	
76	# ls /sys/kernel/debug/batman_adv/bat0/
77	# bla_backbone_table  log                 transtable_global
78	# bla_claim_table     originators         transtable_local
79	# gateways            socket
80	
81	Some of the files contain all sort of status information  regard-
82	ing  the  mesh  network.  For  example, you can view the table of
83	originators (mesh participants) with:
84	
85	# cat /sys/kernel/debug/batman_adv/bat0/originators
86	
87	Other files allow to change batman's behaviour to better fit your
88	requirements.  For instance, you can check the current originator
89	interval (value in milliseconds which determines how often batman
90	sends its broadcast packets):
91	
92	# cat /sys/class/net/bat0/mesh/orig_interval
93	# 1000
94	
95	and also change its value:
96	
97	# echo 3000 > /sys/class/net/bat0/mesh/orig_interval
98	
99	In very mobile scenarios, you might want to adjust the originator
100	interval to a lower value. This will make the mesh  more  respon-
101	sive to topology changes, but will also increase the overhead.
102	
103	
104	USAGE
105	-----
106	
107	To  make use of your newly created mesh, batman advanced provides
108	a new interface "bat0" which you should use from this  point  on.
109	All  interfaces  added  to  batman  advanced are not relevant any
110	longer because batman handles them for you. Basically, one "hands
111	over" the data by using the batman interface and batman will make
112	sure it reaches its destination.
113	
114	The "bat0" interface can be used like any  other  regular  inter-
115	face.  It needs an IP address which can be either statically con-
116	figured or dynamically (by using DHCP or similar services):
117	
118	# NodeA: ifconfig bat0 192.168.0.1
119	# NodeB: ifconfig bat0 192.168.0.2
120	# NodeB: ping 192.168.0.1
121	
122	Note:  In  order to avoid problems remove all IP addresses previ-
123	ously assigned to interfaces now used by batman advanced, e.g.
124	
125	# ifconfig eth0 0.0.0.0
126	
127	
128	LOGGING/DEBUGGING
129	-----------------
130	
131	All error messages, warnings and information messages are sent to
132	the kernel log. Depending on your operating  system  distribution
133	this  can  be read in one of a number of ways. Try using the com-
134	mands: dmesg, logread, or looking in the files  /var/log/kern.log
135	or  /var/log/syslog.  All  batman-adv  messages are prefixed with
136	"batman-adv:" So to see just these messages try
137	
138	# dmesg | grep batman-adv
139	
140	When investigating problems with your mesh network  it  is  some-
141	times  necessary  to see more detail debug messages. This must be
142	enabled when compiling the batman-adv module. When building  bat-
143	man-adv  as  part of kernel, use "make menuconfig" and enable the
144	option "B.A.T.M.A.N. debugging".
145	
146	Those additional  debug messages can be accessed  using a special
147	file in debugfs
148	
149	# cat /sys/kernel/debug/batman_adv/bat0/log
150	
151	The additional debug output is by default disabled. It can be en-
152	abled  during run time. Following log_levels are defined:
153	
154	0 - All  debug  output  disabled
155	1 - Enable messages related to routing / flooding / broadcasting
156	2 - Enable messages related to route added / changed / deleted
157	4 - Enable messages related to translation table operations
158	8 - Enable messages related to bridge loop avoidance
159	16 - Enable messaged related to DAT, ARP snooping and parsing
160	31 - Enable all messages
161	
162	The debug output can be changed at runtime  using  the  file
163	/sys/class/net/bat0/mesh/log_level. e.g.
164	
165	# echo 6 > /sys/class/net/bat0/mesh/log_level
166	
167	will enable debug messages for when routes change.
168	
169	Counters for different types of packets entering and leaving the
170	batman-adv module are available through ethtool:
171	
172	# ethtool --statistics bat0
173	
174	
175	BATCTL
176	------
177	
178	As batman advanced operates on layer 2 all hosts participating in
179	the  virtual switch are completely transparent for all  protocols
180	above layer 2. Therefore the common diagnosis tools do  not  work
181	as  expected.  To  overcome these problems batctl was created. At
182	the  moment the  batctl contains ping,  traceroute,  tcpdump  and
183	interfaces to the kernel module settings.
184	
185	For more information, please see the manpage (man batctl).
186	
187	batctl is available on http://www.open-mesh.org/
188	
189	
190	CONTACT
191	-------
192	
193	Please send us comments, experiences, questions, anything :)
194	
195	IRC:            #batman   on   irc.freenode.org
196	Mailing-list:   b.a.t.m.a.n@open-mesh.org (optional  subscription
197	          at https://lists.open-mesh.org/mm/listinfo/b.a.t.m.a.n)
198	
199	You can also contact the Authors:
200	
201	Marek  Lindner  <mareklindner@neomailbox.ch>
202	Simon  Wunderlich  <sw@simonwunderlich.de>
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