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Based on kernel version 4.15. Page generated on 2018-01-29 10:00 EST.

1	==========
2	batman-adv
3	==========
4	
5	Batman advanced is a new approach to wireless networking which does no longer
6	operate on the IP basis. Unlike the batman daemon, which exchanges information
7	using UDP packets and sets routing tables, batman-advanced operates on ISO/OSI
8	Layer 2 only and uses and routes (or better: bridges) Ethernet Frames. It
9	emulates a virtual network switch of all nodes participating. Therefore all
10	nodes appear to be link local, thus all higher operating protocols won't be
11	affected by any changes within the network. You can run almost any protocol
12	above batman advanced, prominent examples are: IPv4, IPv6, DHCP, IPX.
13	
14	Batman advanced was implemented as a Linux kernel driver to reduce the overhead
15	to a minimum. It does not depend on any (other) network driver, and can be used
16	on wifi as well as ethernet lan, vpn, etc ... (anything with ethernet-style
17	layer 2).
18	
19	
20	Configuration
21	=============
22	
23	Load the batman-adv module into your kernel::
24	
25	  $ insmod batman-adv.ko
26	
27	The module is now waiting for activation. You must add some interfaces on which
28	batman can operate. After loading the module batman advanced will scan your
29	systems interfaces to search for compatible interfaces. Once found, it will
30	create subfolders in the ``/sys`` directories of each supported interface,
31	e.g.::
32	
33	  $ ls /sys/class/net/eth0/batman_adv/
34	  elp_interval iface_status mesh_iface throughput_override
35	
36	If an interface does not have the ``batman_adv`` subfolder, it probably is not
37	supported. Not supported interfaces are: loopback, non-ethernet and batman's
38	own interfaces.
39	
40	Note: After the module was loaded it will continuously watch for new
41	interfaces to verify the compatibility. There is no need to reload the module
42	if you plug your USB wifi adapter into your machine after batman advanced was
43	initially loaded.
44	
45	The batman-adv soft-interface can be created using the iproute2 tool ``ip``::
46	
47	  $ ip link add name bat0 type batadv
48	
49	To activate a given interface simply attach it to the ``bat0`` interface::
50	
51	  $ ip link set dev eth0 master bat0
52	
53	Repeat this step for all interfaces you wish to add. Now batman starts
54	using/broadcasting on this/these interface(s).
55	
56	By reading the "iface_status" file you can check its status::
57	
58	  $ cat /sys/class/net/eth0/batman_adv/iface_status
59	  active
60	
61	To deactivate an interface you have to detach it from the "bat0" interface::
62	
63	  $ ip link set dev eth0 nomaster
64	
65	
66	All mesh wide settings can be found in batman's own interface folder::
67	
68	  $ ls /sys/class/net/bat0/mesh/
69	  aggregated_ogms       fragmentation isolation_mark routing_algo
70	  ap_isolation          gw_bandwidth  log_level      vlan0
71	  bonding               gw_mode       multicast_mode
72	  bridge_loop_avoidance gw_sel_class  network_coding
73	  distributed_arp_table hop_penalty   orig_interval
74	
75	There is a special folder for debugging information::
76	
77	  $ ls /sys/kernel/debug/batman_adv/bat0/
78	  bla_backbone_table log         neighbors         transtable_local
79	  bla_claim_table    mcast_flags originators
80	  dat_cache          nc          socket
81	  gateways           nc_nodes    transtable_global
82	
83	Some of the files contain all sort of status information regarding the mesh
84	network. For example, you can view the table of originators (mesh
85	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 requirements.
90	For instance, you can check the current originator interval (value in
91	milliseconds which determines how often batman sends its broadcast packets)::
92	
93	  $ cat /sys/class/net/bat0/mesh/orig_interval
94	  1000
95	
96	and also change its value::
97	
98	  $ echo 3000 > /sys/class/net/bat0/mesh/orig_interval
99	
100	In very mobile scenarios, you might want to adjust the originator interval to a
101	lower value. This will make the mesh more responsive to topology changes, but
102	will also increase the overhead.
103	
104	
105	Usage
106	=====
107	
108	To make use of your newly created mesh, batman advanced provides a new
109	interface "bat0" which you should use from this point on. All interfaces added
110	to batman advanced are not relevant any longer because batman handles them for
111	you. Basically, one "hands over" the data by using the batman interface and
112	batman will make sure it reaches its destination.
113	
114	The "bat0" interface can be used like any other regular interface. It needs an
115	IP address which can be either statically configured or dynamically (by using
116	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 previously assigned to
126	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 the kernel
135	log. Depending on your operating system distribution this can be read in one of
136	a number of ways. Try using the commands: ``dmesg``, ``logread``, or looking in
137	the files ``/var/log/kern.log`` or ``/var/log/syslog``. All batman-adv messages
138	are prefixed with "batman-adv:" So to see just these messages try::
139	
140	  $ dmesg | grep batman-adv
141	
142	When investigating problems with your mesh network, it is sometimes necessary to
143	see more detail debug messages. This must be enabled when compiling the
144	batman-adv module. When building batman-adv as part of kernel, use "make
145	menuconfig" and enable the option ``B.A.T.M.A.N. debugging``
146	(``CONFIG_BATMAN_ADV_DEBUG=y``).
147	
148	Those additional debug messages can be accessed using a special file in
149	debugfs::
150	
151	  $ cat /sys/kernel/debug/batman_adv/bat0/log
152	
153	The additional debug output is by default disabled. It can be enabled during
154	run time. Following log_levels are defined:
155	
156	.. flat-table::
157	
158	   * - 0
159	     - All debug output disabled
160	   * - 1
161	     - Enable messages related to routing / flooding / broadcasting
162	   * - 2
163	     - Enable messages related to route added / changed / deleted
164	   * - 4
165	     - Enable messages related to translation table operations
166	   * - 8
167	     - Enable messages related to bridge loop avoidance
168	   * - 16
169	     - Enable messages related to DAT, ARP snooping and parsing
170	   * - 32
171	     - Enable messages related to network coding
172	   * - 64
173	     - Enable messages related to multicast
174	   * - 128
175	     - Enable messages related to throughput meter
176	   * - 255
177	     - Enable all messages
178	
179	The debug output can be changed at runtime using the file
180	``/sys/class/net/bat0/mesh/log_level``. e.g.::
181	
182	  $ echo 6 > /sys/class/net/bat0/mesh/log_level
183	
184	will enable debug messages for when routes change.
185	
186	Counters for different types of packets entering and leaving the batman-adv
187	module are available through ethtool::
188	
189	  $ ethtool --statistics bat0
190	
191	
192	batctl
193	======
194	
195	As batman advanced operates on layer 2, all hosts participating in the virtual
196	switch are completely transparent for all protocols above layer 2. Therefore
197	the common diagnosis tools do not work as expected. To overcome these problems,
198	batctl was created. At the moment the batctl contains ping, traceroute, tcpdump
199	and interfaces to the kernel module settings.
200	
201	For more information, please see the manpage (``man batctl``).
202	
203	batctl is available on https://www.open-mesh.org/
204	
205	
206	Contact
207	=======
208	
209	Please send us comments, experiences, questions, anything :)
210	
211	IRC:
212	  #batman on irc.freenode.org
213	Mailing-list:
214	  b.a.t.m.a.n@open-mesh.org (optional subscription at
215	  https://lists.open-mesh.org/mm/listinfo/b.a.t.m.a.n)
216	
217	You can also contact the Authors:
218	
219	* Marek Lindner <mareklindner@neomailbox.ch>
220	* Simon Wunderlich <sw@simonwunderlich.de>
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