Documentation/networking/batman-adv.rst - LeafOS-Devices/android_kernel_samsung_exynos9820 - Gitiles

 ==========
 batman-adv
 ==========

 Batman advanced is a new approach to wireless networking which does no longer
 operate on the IP basis. Unlike the batman daemon, which exchanges information
 using UDP packets and sets routing tables, batman-advanced operates on ISO/OSI
 Layer 2 only and uses and routes (or better: bridges) Ethernet Frames. It
 emulates a virtual network switch of all nodes participating. Therefore all
 nodes appear to be link local, thus all higher operating protocols won't be
 affected by any changes within the network. You can run almost any protocol
 above batman advanced, prominent examples are: IPv4, IPv6, DHCP, IPX.

 Batman advanced was implemented as a Linux kernel driver to reduce the overhead
 to a minimum. It does not depend on any (other) network driver, and can be used
 on wifi as well as ethernet lan, vpn, etc ... (anything with ethernet-style
 layer 2).


 Configuration
 =============

 Load the batman-adv module into your kernel::

   $ insmod batman-adv.ko

 The module is now waiting for activation. You must add some interfaces on which
 batman can operate. After loading the module batman advanced will scan your
 systems interfaces to search for compatible interfaces. Once found, it will
 create subfolders in the ``/sys`` directories of each supported interface,
 e.g.::

   $ ls /sys/class/net/eth0/batman_adv/
   elp_interval iface_status mesh_iface throughput_override

 If an interface does not have the ``batman_adv`` subfolder, it probably is not
 supported. Not supported interfaces are: loopback, non-ethernet and batman's
 own interfaces.

 Note: After the module was loaded it will continuously watch for new
 interfaces to verify the compatibility. There is no need to reload the module
 if you plug your USB wifi adapter into your machine after batman advanced was
 initially loaded.

 The batman-adv soft-interface can be created using the iproute2 tool ``ip``::

   $ ip link add name bat0 type batadv

 To activate a given interface simply attach it to the ``bat0`` interface::

   $ ip link set dev eth0 master bat0

 Repeat this step for all interfaces you wish to add. Now batman starts
 using/broadcasting on this/these interface(s).

 By reading the "iface_status" file you can check its status::

   $ cat /sys/class/net/eth0/batman_adv/iface_status
   active

 To deactivate an interface you have to detach it from the "bat0" interface::

   $ ip link set dev eth0 nomaster


 All mesh wide settings can be found in batman's own interface folder::

   $ ls /sys/class/net/bat0/mesh/
   aggregated_ogms       fragmentation isolation_mark routing_algo
   ap_isolation          gw_bandwidth  log_level      vlan0
   bonding               gw_mode       multicast_mode
   bridge_loop_avoidance gw_sel_class  network_coding
   distributed_arp_table hop_penalty   orig_interval

 There is a special folder for debugging information::

   $ ls /sys/kernel/debug/batman_adv/bat0/
   bla_backbone_table log         neighbors         transtable_local
   bla_claim_table    mcast_flags originators
   dat_cache          nc          socket
   gateways           nc_nodes    transtable_global

 Some of the files contain all sort of status information regarding the mesh
 network. For example, you can view the table of originators (mesh
 participants) with::

   $ cat /sys/kernel/debug/batman_adv/bat0/originators

 Other files allow to change batman's behaviour to better fit your requirements.
 For instance, you can check the current originator interval (value in
 milliseconds which determines how often batman sends its broadcast packets)::

   $ cat /sys/class/net/bat0/mesh/orig_interval
   1000

 and also change its value::

   $ echo 3000 > /sys/class/net/bat0/mesh/orig_interval

 In very mobile scenarios, you might want to adjust the originator interval to a
 lower value. This will make the mesh more responsive to topology changes, but
 will also increase the overhead.


 Usage
 =====

 To make use of your newly created mesh, batman advanced provides a new
 interface "bat0" which you should use from this point on. All interfaces added
 to batman advanced are not relevant any longer because batman handles them for
 you. Basically, one "hands over" the data by using the batman interface and
 batman will make sure it reaches its destination.

 The "bat0" interface can be used like any other regular interface. It needs an
 IP address which can be either statically configured or dynamically (by using
 DHCP or similar services)::

   NodeA: ip link set up dev bat0
   NodeA: ip addr add 192.168.0.1/24 dev bat0

   NodeB: ip link set up dev bat0
   NodeB: ip addr add 192.168.0.2/24 dev bat0
   NodeB: ping 192.168.0.1

 Note: In order to avoid problems remove all IP addresses previously assigned to
 interfaces now used by batman advanced, e.g.::

   $ ip addr flush dev eth0


 Logging/Debugging
 =================

 All error messages, warnings and information messages are sent to the kernel
 log. Depending on your operating system distribution this can be read in one of
 a number of ways. Try using the commands: ``dmesg``, ``logread``, or looking in
 the files ``/var/log/kern.log`` or ``/var/log/syslog``. All batman-adv messages
 are prefixed with "batman-adv:" So to see just these messages try::

   $ dmesg | grep batman-adv

 When investigating problems with your mesh network, it is sometimes necessary to
 see more detail debug messages. This must be enabled when compiling the
 batman-adv module. When building batman-adv as part of kernel, use "make
 menuconfig" and enable the option ``B.A.T.M.A.N. debugging``
 (``CONFIG_BATMAN_ADV_DEBUG=y``).

 Those additional debug messages can be accessed using a special file in
 debugfs::

   $ cat /sys/kernel/debug/batman_adv/bat0/log

 The additional debug output is by default disabled. It can be enabled during
 run time. Following log_levels are defined:

 .. flat-table::

    * - 0
      - All debug output disabled
    * - 1
      - Enable messages related to routing / flooding / broadcasting
    * - 2
      - Enable messages related to route added / changed / deleted
    * - 4
      - Enable messages related to translation table operations
    * - 8
      - Enable messages related to bridge loop avoidance
    * - 16
      - Enable messages related to DAT, ARP snooping and parsing
    * - 32
      - Enable messages related to network coding
    * - 64
      - Enable messages related to multicast
    * - 128
      - Enable messages related to throughput meter
    * - 255
      - Enable all messages

 The debug output can be changed at runtime using the file
 ``/sys/class/net/bat0/mesh/log_level``. e.g.::

   $ echo 6 > /sys/class/net/bat0/mesh/log_level

 will enable debug messages for when routes change.

 Counters for different types of packets entering and leaving the batman-adv
 module are available through ethtool::

   $ ethtool --statistics bat0


 batctl
 ======

 As batman advanced operates on layer 2, all hosts participating in the virtual
 switch are completely transparent for all protocols above layer 2. Therefore
 the common diagnosis tools do not work as expected. To overcome these problems,
 batctl was created. At the moment the batctl contains ping, traceroute, tcpdump
 and interfaces to the kernel module settings.

 For more information, please see the manpage (``man batctl``).

 batctl is available on https://www.open-mesh.org/


 Contact
 =======

 Please send us comments, experiences, questions, anything :)

 IRC:
   #batman on irc.freenode.org
 Mailing-list:
   b.a.t.m.a.n@open-mesh.org (optional subscription at
   https://lists.open-mesh.org/mm/listinfo/b.a.t.m.a.n)

 You can also contact the Authors:

 * Marek Lindner <mareklindner@neomailbox.ch>
 * Simon Wunderlich <sw@simonwunderlich.de>
	==========
	batman-adv
	==========

	Batman advanced is a new approach to wireless networking which does no longer
	operate on the IP basis. Unlike the batman daemon, which exchanges information
	using UDP packets and sets routing tables, batman-advanced operates on ISO/OSI
	Layer 2 only and uses and routes (or better: bridges) Ethernet Frames. It
	emulates a virtual network switch of all nodes participating. Therefore all
	nodes appear to be link local, thus all higher operating protocols won't be
	affected by any changes within the network. You can run almost any protocol
	above batman advanced, prominent examples are: IPv4, IPv6, DHCP, IPX.

	Batman advanced was implemented as a Linux kernel driver to reduce the overhead
	to a minimum. It does not depend on any (other) network driver, and can be used
	on wifi as well as ethernet lan, vpn, etc ... (anything with ethernet-style
	layer 2).


	Configuration
	=============

	Load the batman-adv module into your kernel::

	$ insmod batman-adv.ko

	The module is now waiting for activation. You must add some interfaces on which
	batman can operate. After loading the module batman advanced will scan your
	systems interfaces to search for compatible interfaces. Once found, it will
	create subfolders in the ``/sys`` directories of each supported interface,
	e.g.::

	$ ls /sys/class/net/eth0/batman_adv/
	elp_interval iface_status mesh_iface throughput_override

	If an interface does not have the ``batman_adv`` subfolder, it probably is not
	supported. Not supported interfaces are: loopback, non-ethernet and batman's
	own interfaces.

	Note: After the module was loaded it will continuously watch for new
	interfaces to verify the compatibility. There is no need to reload the module
	if you plug your USB wifi adapter into your machine after batman advanced was
	initially loaded.

	The batman-adv soft-interface can be created using the iproute2 tool ``ip``::

	$ ip link add name bat0 type batadv

	To activate a given interface simply attach it to the ``bat0`` interface::

	$ ip link set dev eth0 master bat0

	Repeat this step for all interfaces you wish to add. Now batman starts
	using/broadcasting on this/these interface(s).

	By reading the "iface_status" file you can check its status::

	$ cat /sys/class/net/eth0/batman_adv/iface_status
	active

	To deactivate an interface you have to detach it from the "bat0" interface::

	$ ip link set dev eth0 nomaster


	All mesh wide settings can be found in batman's own interface folder::

	$ ls /sys/class/net/bat0/mesh/
	aggregated_ogms fragmentation isolation_mark routing_algo
	ap_isolation gw_bandwidth log_level vlan0
	bonding gw_mode multicast_mode
	bridge_loop_avoidance gw_sel_class network_coding
	distributed_arp_table hop_penalty orig_interval

	There is a special folder for debugging information::

	$ ls /sys/kernel/debug/batman_adv/bat0/
	bla_backbone_table log neighbors transtable_local
	bla_claim_table mcast_flags originators
	dat_cache nc socket
	gateways nc_nodes transtable_global

	Some of the files contain all sort of status information regarding the mesh
	network. For example, you can view the table of originators (mesh
	participants) with::

	$ cat /sys/kernel/debug/batman_adv/bat0/originators

	Other files allow to change batman's behaviour to better fit your requirements.
	For instance, you can check the current originator interval (value in
	milliseconds which determines how often batman sends its broadcast packets)::

	$ cat /sys/class/net/bat0/mesh/orig_interval
	1000

	and also change its value::

	$ echo 3000 > /sys/class/net/bat0/mesh/orig_interval

	In very mobile scenarios, you might want to adjust the originator interval to a
	lower value. This will make the mesh more responsive to topology changes, but
	will also increase the overhead.


	Usage
	=====

	To make use of your newly created mesh, batman advanced provides a new
	interface "bat0" which you should use from this point on. All interfaces added
	to batman advanced are not relevant any longer because batman handles them for
	you. Basically, one "hands over" the data by using the batman interface and
	batman will make sure it reaches its destination.

	The "bat0" interface can be used like any other regular interface. It needs an
	IP address which can be either statically configured or dynamically (by using
	DHCP or similar services)::

	NodeA: ip link set up dev bat0
	NodeA: ip addr add 192.168.0.1/24 dev bat0

	NodeB: ip link set up dev bat0
	NodeB: ip addr add 192.168.0.2/24 dev bat0
	NodeB: ping 192.168.0.1

	Note: In order to avoid problems remove all IP addresses previously assigned to
	interfaces now used by batman advanced, e.g.::

	$ ip addr flush dev eth0


	Logging/Debugging
	=================

	All error messages, warnings and information messages are sent to the kernel
	log. Depending on your operating system distribution this can be read in one of
	a number of ways. Try using the commands: ``dmesg``, ``logread``, or looking in
	the files ``/var/log/kern.log`` or ``/var/log/syslog``. All batman-adv messages
	are prefixed with "batman-adv:" So to see just these messages try::

	$ dmesg \| grep batman-adv

	When investigating problems with your mesh network, it is sometimes necessary to
	see more detail debug messages. This must be enabled when compiling the
	batman-adv module. When building batman-adv as part of kernel, use "make
	menuconfig" and enable the option ``B.A.T.M.A.N. debugging``
	(``CONFIG_BATMAN_ADV_DEBUG=y``).

	Those additional debug messages can be accessed using a special file in
	debugfs::

	$ cat /sys/kernel/debug/batman_adv/bat0/log

	The additional debug output is by default disabled. It can be enabled during
	run time. Following log_levels are defined:

	.. flat-table::

	* - 0
	- All debug output disabled
	* - 1
	- Enable messages related to routing / flooding / broadcasting
	* - 2
	- Enable messages related to route added / changed / deleted
	* - 4
	- Enable messages related to translation table operations
	* - 8
	- Enable messages related to bridge loop avoidance
	* - 16
	- Enable messages related to DAT, ARP snooping and parsing
	* - 32
	- Enable messages related to network coding
	* - 64
	- Enable messages related to multicast
	* - 128
	- Enable messages related to throughput meter
	* - 255
	- Enable all messages

	The debug output can be changed at runtime using the file
	``/sys/class/net/bat0/mesh/log_level``. e.g.::

	$ echo 6 > /sys/class/net/bat0/mesh/log_level

	will enable debug messages for when routes change.

	Counters for different types of packets entering and leaving the batman-adv
	module are available through ethtool::

	$ ethtool --statistics bat0


	batctl
	======

	As batman advanced operates on layer 2, all hosts participating in the virtual
	switch are completely transparent for all protocols above layer 2. Therefore
	the common diagnosis tools do not work as expected. To overcome these problems,
	batctl was created. At the moment the batctl contains ping, traceroute, tcpdump
	and interfaces to the kernel module settings.

	For more information, please see the manpage (``man batctl``).

	batctl is available on https://www.open-mesh.org/


	Contact
	=======

	Please send us comments, experiences, questions, anything :)

	IRC:
	#batman on irc.freenode.org
	Mailing-list:
	b.a.t.m.a.n@open-mesh.org (optional subscription at
	https://lists.open-mesh.org/mm/listinfo/b.a.t.m.a.n)

	You can also contact the Authors:

	* Marek Lindner <mareklindner@neomailbox.ch>
	* Simon Wunderlich <sw@simonwunderlich.de>