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Based on kernel version 4.7.2. Page generated on 2016-08-22 22:47 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: ip link set up dev bat0
119	# NodeA: ip addr add 192.168.0.1/24 dev bat0
120	
121	# NodeB: ip link set up dev bat0
122	# NodeB: ip addr add 192.168.0.2/24 dev bat0
123	# NodeB: ping 192.168.0.1
124	
125	Note:  In  order to avoid problems remove all IP addresses previ-
126	ously assigned to interfaces now used by batman advanced, e.g.
127	
128	# ip addr flush dev eth0
129	
130	
131	LOGGING/DEBUGGING
132	-----------------
133	
134	All error messages, warnings and information messages are sent to
135	the kernel log. Depending on your operating  system  distribution
136	this  can  be read in one of a number of ways. Try using the com-
137	mands: dmesg, logread, or looking in the files  /var/log/kern.log
138	or  /var/log/syslog.  All  batman-adv  messages are prefixed with
139	"batman-adv:" So to see just these messages try
140	
141	# dmesg | grep batman-adv
142	
143	When investigating problems with your mesh network  it  is  some-
144	times  necessary  to see more detail debug messages. This must be
145	enabled when compiling the batman-adv module. When building  bat-
146	man-adv  as  part of kernel, use "make menuconfig" and enable the
147	option "B.A.T.M.A.N. debugging".
148	
149	Those additional  debug messages can be accessed  using a special
150	file in debugfs
151	
152	# cat /sys/kernel/debug/batman_adv/bat0/log
153	
154	The additional debug output is by default disabled. It can be en-
155	abled  during run time. Following log_levels are defined:
156	
157	0 - All  debug  output  disabled
158	1 - Enable messages related to routing / flooding / broadcasting
159	2 - Enable messages related to route added / changed / deleted
160	4 - Enable messages related to translation table operations
161	8 - Enable messages related to bridge loop avoidance
162	16 - Enable messaged related to DAT, ARP snooping and parsing
163	31 - Enable all messages
164	
165	The debug output can be changed at runtime  using  the  file
166	/sys/class/net/bat0/mesh/log_level. e.g.
167	
168	# echo 6 > /sys/class/net/bat0/mesh/log_level
169	
170	will enable debug messages for when routes change.
171	
172	Counters for different types of packets entering and leaving the
173	batman-adv module are available through ethtool:
174	
175	# ethtool --statistics bat0
176	
177	
178	BATCTL
179	------
180	
181	As batman advanced operates on layer 2 all hosts participating in
182	the  virtual switch are completely transparent for all  protocols
183	above layer 2. Therefore the common diagnosis tools do  not  work
184	as  expected.  To  overcome these problems batctl was created. At
185	the  moment the  batctl contains ping,  traceroute,  tcpdump  and
186	interfaces to the kernel module settings.
187	
188	For more information, please see the manpage (man batctl).
189	
190	batctl is available on https://www.open-mesh.org/
191	
192	
193	CONTACT
194	-------
195	
196	Please send us comments, experiences, questions, anything :)
197	
198	IRC:            #batman   on   irc.freenode.org
199	Mailing-list:   b.a.t.m.a.n@open-mesh.org (optional  subscription
200	          at https://lists.open-mesh.org/mm/listinfo/b.a.t.m.a.n)
201	
202	You can also contact the Authors:
203	
204	Marek  Lindner  <mareklindner@neomailbox.ch>
205	Simon  Wunderlich  <sw@simonwunderlich.de>
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