1BATMAN-ADV 2---------- 3 4Batman advanced is a new approach to wireless networking which 5does no longer operate on the IP basis. Unlike the batman daemon, 6which exchanges information using UDP packets and sets routing 7tables, batman-advanced operates on ISO/OSI Layer 2 only and uses 8and routes (or better: bridges) Ethernet Frames. It emulates a 9virtual network switch of all nodes participating. Therefore all 10nodes appear to be link local, thus all higher operating proto- 11cols won't be affected by any changes within the network. You can 12run almost any protocol above batman advanced, prominent examples 13are: IPv4, IPv6, DHCP, IPX. 14 15Batman advanced was implemented as a Linux kernel driver to re- 16duce the overhead to a minimum. It does not depend on any (other) 17network driver, and can be used on wifi as well as ethernet lan, 18vpn, etc ... (anything with ethernet-style layer 2). 19 20 21CONFIGURATION 22------------- 23 24Load the batman-adv module into your kernel: 25 26# insmod batman-adv.ko 27 28The module is now waiting for activation. You must add some in- 29terfaces on which batman can operate. After loading the module 30batman advanced will scan your systems interfaces to search for 31compatible interfaces. Once found, it will create subfolders in 32the /sys directories of each supported interface, e.g. 33 34# ls /sys/class/net/eth0/batman_adv/ 35# iface_status mesh_iface 36 37If an interface does not have the "batman_adv" subfolder it prob- 38ably is not supported. Not supported interfaces are: loopback, 39non-ethernet and batman's own interfaces. 40 41Note: After the module was loaded it will continuously watch for 42new interfaces to verify the compatibility. There is no need to 43reload the module if you plug your USB wifi adapter into your ma- 44chine after batman advanced was initially loaded. 45 46To 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 51Repeat this step for all interfaces you wish to add. Now batman 52starts using/broadcasting on this/these interface(s). 53 54By reading the "iface_status" file you can check its status: 55 56# cat /sys/class/net/eth0/batman_adv/iface_status 57# active 58 59To 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 65All mesh wide settings can be found in batman's own interface 66folder: 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 74There 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 81Some of the files contain all sort of status information regard- 82ing the mesh network. For example, you can view the table of 83originators (mesh participants) with: 84 85# cat /sys/kernel/debug/batman_adv/bat0/originators 86 87Other files allow to change batman's behaviour to better fit your 88requirements. For instance, you can check the current originator 89interval (value in milliseconds which determines how often batman 90sends its broadcast packets): 91 92# cat /sys/class/net/bat0/mesh/orig_interval 93# 1000 94 95and also change its value: 96 97# echo 3000 > /sys/class/net/bat0/mesh/orig_interval 98 99In very mobile scenarios, you might want to adjust the originator 100interval to a lower value. This will make the mesh more respon- 101sive to topology changes, but will also increase the overhead. 102 103 104USAGE 105----- 106 107To make use of your newly created mesh, batman advanced provides 108a new interface "bat0" which you should use from this point on. 109All interfaces added to batman advanced are not relevant any 110longer because batman handles them for you. Basically, one "hands 111over" the data by using the batman interface and batman will make 112sure it reaches its destination. 113 114The "bat0" interface can be used like any other regular inter- 115face. It needs an IP address which can be either statically con- 116figured 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 122Note: In order to avoid problems remove all IP addresses previ- 123ously assigned to interfaces now used by batman advanced, e.g. 124 125# ifconfig eth0 0.0.0.0 126 127 128LOGGING/DEBUGGING 129----------------- 130 131All error messages, warnings and information messages are sent to 132the kernel log. Depending on your operating system distribution 133this can be read in one of a number of ways. Try using the com- 134mands: dmesg, logread, or looking in the files /var/log/kern.log 135or /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 140When investigating problems with your mesh network it is some- 141times necessary to see more detail debug messages. This must be 142enabled when compiling the batman-adv module. When building bat- 143man-adv as part of kernel, use "make menuconfig" and enable the 144option "B.A.T.M.A.N. debugging". 145 146Those additional debug messages can be accessed using a special 147file in debugfs 148 149# cat /sys/kernel/debug/batman_adv/bat0/log 150 151The additional debug output is by default disabled. It can be en- 152abled during run time. Following log_levels are defined: 153 1540 - All debug output disabled 1551 - Enable messages related to routing / flooding / broadcasting 1562 - Enable messages related to route added / changed / deleted 1574 - Enable messages related to translation table operations 1588 - Enable messages related to bridge loop avoidance 15916 - Enable messaged related to DAT, ARP snooping and parsing 16031 - Enable all messages 161 162The 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 167will enable debug messages for when routes change. 168 169Counters for different types of packets entering and leaving the 170batman-adv module are available through ethtool: 171 172# ethtool --statistics bat0 173 174 175BATCTL 176------ 177 178As batman advanced operates on layer 2 all hosts participating in 179the virtual switch are completely transparent for all protocols 180above layer 2. Therefore the common diagnosis tools do not work 181as expected. To overcome these problems batctl was created. At 182the moment the batctl contains ping, traceroute, tcpdump and 183interfaces to the kernel module settings. 184 185For more information, please see the manpage (man batctl). 186 187batctl is available on http://www.open-mesh.org/ 188 189 190CONTACT 191------- 192 193Please send us comments, experiences, questions, anything :) 194 195IRC: #batman on irc.freenode.org 196Mailing-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 199You can also contact the Authors: 200 201Marek Lindner <mareklindner@neomailbox.ch> 202Simon Wunderlich <sw@simonwunderlich.de> 203