Repository : ssh://git@diktynna/doc

On branch : main

commit 64b6ae5ab94ec5a73ee2a22e53b1873fb952dfb6 Merge: 4024e8c3 a79cd04f Author: Sven Eckelmann sven@narfation.org Date: Sat Jul 10 16:26:55 2021 +0200

Merge branch 'backup-redmine/2021-07-10'

64b6ae5ab94ec5a73ee2a22e53b1873fb952dfb6 batman-adv/Building-with-openwrt.rst | 6 ------ batman-adv/Faq.rst | 8 ++++---- batmand/Faq.rst | 6 +++--- open-mesh/IRC.rst | 4 ++-- 4 files changed, 9 insertions(+), 15 deletions(-)

diff --cc batman-adv/Building-with-openwrt.rst index 9f103f05,00000000..67a05b5d mode 100644,000000..100644 --- a/batman-adv/Building-with-openwrt.rst +++ b/batman-adv/Building-with-openwrt.rst @@@ -1,260 -1,0 +1,254 @@@ +.. SPDX-License-Identifier: GPL-2.0 + +Building B.A.T.M.A.N. Advanced with Openwrt +=========================================== + +Many tutorials assume that you have batman-adv running on an Openwrt +system without going into detail how to get the system built and +configured. This documents aims to fill the gap by providing a +step-by-step explanation how to get your Openwrt system up & running. + +Getting the Openwrt build environment +------------------------------------- + +First, you need to obtain a copy of the Openwrt build system which +contains all the build information to compile & package a complete Linux +system. You can either clone the sources via git or get tarballs from +the Openwrt project website. The various versions of Openwrt (bleeding +edge 'trunk', last stable release, previous release, etc) can be +downloaded directly from the `Openwrt +repositories https://dev.openwrt.org/wiki/GetSource`__. + +Once downloaded change into the Openwrt directory and configure the +system to meet you needs (e.g. choose the platform and additional +packages you intend to use). + +:: + + cd openwrt + make menuconfig + +*Note*: The batman-adv package is not there yet because it needs to be +activated separately (see the following steps). + +To build your images you always have to invoke the "make" command from +within the Openwrt folder: + +:: + + cd openwrt + make + +The rest of the document will focus on the batman-adv package. It is +assumed that you configured the system to work on your platform. If you +require additional information on how to tweak your Openwrt system, +please see `the Openwrt project website https://www.openwrt.org`__. + +Adding the batman-adv / batctl package +-------------------------------------- + +The standard Openwrt package feed contains a batman-adv and a batctl +package which is intended to be used on a day to day basis, therefore it +retrieves the latest batman-adv / batctl stable release. Since a lot of +people want to experiment with the latest features or use Openwrt to +test their own batman-adv patches we also provide an Openwrt package +feed which contains the batman-adv development version. + +stable version: + +:: + + scripts/feeds update + scripts/feeds install kmod-batman-adv + scripts/feeds install batctl + - *Note*: If you downloaded an Openwrt release but intend to build the - latest batman-adv package you might need to modify your - feeds.conf(.default). Make sure you have "src-git routing - git://github.com/openwrt-routing/packages.git" instead of e.g. "src-git - routing git://github.com/openwrt-routing/packages.git;for-12.09.x". - +developer version: + +Append the following line to your Openwrt feed configuration file +(either feeds.conf or feeds.conf.default): + +:: + + src-git batman https://git.open-mesh.org/openwrt-feed-devel.git + +Update the package information and add the development package: + +:: + + scripts/feeds update + scripts/feeds install kmod-batman-adv-devel + scripts/feeds install batctl-devel + +Configuring the batman-adv package +---------------------------------- + +As soon as the batman-adv package has been added, it will show up in the +Openwrt package menu: + +stable version: + +:: + + Kernel modules ---> + Network Support ---> + kmod-batman-adv + +developer version: + +:: + + Kernel modules ---> + Network Support ---> + kmod-batman-adv-devel + +Once the package had been selected a number of suboptions will become +visible. You can enable/disable the verbose debug logging as well as +choose whether or not to include the batctl tool. + +In addition, the batman-adv package comes with an init script which is +installed per default. This script will run at boot time and can be used +to configure your desired batman-adv options. It reads the batman-adv +uci file to retrieve the settings which allows to specify interfaces, +intervals, log level and more. + +Basic configuration: :doc:`batman-adv Openwrt config <Batman-adv-openwrt-config>` + +Rebuilding the package +---------------------- + +If you experience build problems or simply intend to rebuild the +batman-adv package only, you can tell Openwrt to build a specific +package and enable the debugging mode as follows: + +stable version: + +:: + + cd openwrt + make package/batman-adv/clean + make package/batman-adv/compile V=99 + +developer version: + +:: + + cd openwrt + make package/batman-adv-devel/clean + make package/batman-adv-devel/compile V=99 + +Applying patches +---------------- + +The package offers an easy way to apply custom patches whenever +batman-adv is built. Simply copy your patches into the "patches" folder +inside the package directory (you have to create the folder in case it +does not exist yet). Patch files having the string 'batman' in their +name are applied to batman-adv whereas patches containing the string +'batctl' are applied to the batctl tool. The location of the folder +depends on which package you want to patch: + +stable version: + +:: + + openwrt/feeds/packages/net/batman-adv/patches + +developer version: + +:: + + openwrt/feeds/batman/batman-adv-devel/patches + +Changing the batman-adv / batctl version +---------------------------------------- + +It is also possible to modify the batman-adv version if you ever wanted +to build an older/newer version than configured in the package: + +stable version: + +Adjust the PKG_VERSION variable configured in the package Makefile to +download & build the stable release you are interested in. + +cat openwrt/feeds/routing/batman-adv/Makefile + +:: + + [..] + PKG_VERSION:=2013.4.0 + [..] + +you will probably want to change md5sum also: + +:: + + [..] + PKG_MD5SUM:=1a2b3c4d5e6f7g # https://downloads.open-mesh.org/batman/releases/batman-adv-2013.4.0/batman-a... + [..] + +And if you want to match batman-adv version with batctl version, do the +similar thing for the next lines: + +:: + + [..] + BATCTL_VERSION:=2013.4.0 + [..] + +:: + + [..] + PKG_MD5SUM:=1a2b3c4d5e6f7g # https://downloads.open-mesh.org/batman/releases/batman-adv-2013.4.0/batctl-2... + [..] + +And be careful when changing versions, your build may fail. Build with +make V=99 so you can see what is going on, and if applying some +batman-adv patch fails, locate it under +/home/user/openwrt/feeds/routing/batman-adv/patches and remove it. + +developer version: + +Adjust the batman-adv & batctl git branch / tag via the Openwrt +configuration menu (aka "make menuconfig") to download & build the git +revision you are interested in: + +:: + + Kernel modules ---> + Network Support ---> + kmod-batman-adv-devel + batman-adv branch + +Building from a different branch +-------------------------------- + +The developer package offers a convenient way to select another branch +to build from. This is particularly useful for testing features that +have not been merged into the master branch yet. Simply enter the branch +or git tag you wish to build in the Openwrt build menu. + +Kernel crash debug +------------------ + +In case you experience kernel oopses it might prove helpful to enable +the kernel symbol table which translates the cryptic numbers which are +part of each kernel oops log into readable function names. This +calltrace can help developers to analyze the problem. Use Openwrt's +config menu to enable the kernel symbol table and rebuild your image: + +:: + + make menuconfig + Global build settings ---> + Compile the kernel with symbol table information + +If you can't find this option you are using an older Openwrt version +which doesn't offer this config switch in the main menu. You have to +modify the kernel settings directly: + +:: + + make kernel_menuconfig + General setup ---> + Configure standard kernel features (for small systems) ---> + Load all symbols for debugging/ksymoops diff --cc batman-adv/Faq.rst index b7226ed4,00000000..d7f5751e mode 100644,000000..100644 --- a/batman-adv/Faq.rst +++ b/batman-adv/Faq.rst @@@ -1,328 -1,0 +1,328 @@@ +.. SPDX-License-Identifier: GPL-2.0 + +FAQ +=== + +Below you can see a list of frequently asked questions and answers. If +your question is not listed below, please contact us. You can contact us - via IRC: `#batman - channel https://webchat.freenode.net/?channels=batman`__ on - Freenode.org or by sending an e-mail to: b.a.t.m.a.n@lists.open-mesh.org ++via IRC: `#batadv ++channel https://webirc.hackint.org/#ircs://irc.hackint.org/#batadv`__ on ++hackint.org or by sending an e-mail to: b.a.t.m.a.n@lists.open-mesh.org +(only plain-text). + +If you got any problems? See: the :doc:`Troubleshooting <Troubleshooting>` +page. + +.. _batman-adv-faq-batman-general-questions: + +B.A.T.M.A.N. General questions +------------------------------ + +Does B.A.T.M.A.N. have simulator (NS2, Omnet, etc) support? +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +**Q:** Does B.A.T.M.A.N. have its own simulator? + +**A:** At this point no, but B.A.T.M.A.N. implementation (we know of) +supports simulators like the ones mentioned above. However, some +people experiment with B.A.T.M.A.N. using emulators (UML/Qemu/etc). If +you are looking for step-by-step instructions to install such a system +you can :doc:`read our emulation document </open-mesh/Emulation_Environment>`. + +How to make my mesh network secure ? +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +**Q:** Can I make my mesh network secure? + +**A:** This depends on the security you want or need. Security is a +big field. Probably you mean encryption and authentication. + +When you only want to make the whole WLAN stuff unreadable for the +outside, you could just use WPA_NONE or IBSS RSN. But this doesn't +resolve the problem that the key could leak and make the mesh attackable +- but that is something which could always happen. So it is probably not +a solution for WiFi community projects, but for mesh networks controlled +by a company. + +There are other ideas for traffic over batman-adv. Just forget about +encrypting your data on the WiFi layer, but instead do everything some +layers above. Some people experimented with the idea of implementing the +needed authentication and encryption over IPsec. + +And most of the encryption and authentication stuff has to be resolved +by the user and not by the network provider. This means HTTPS for +sensible data instead of HTTP, SSH instead of Telnet, pop3s instead of +pop3 and so on. + +So it really depends what you want and cannot be resolved in a "security +for everything, against any attack and for every purpose" blob. + +Why does batman need so much time to detect a "dead" node? +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +**Q:** Why can I see a node in the originator table a long time after +it died? *Or:* Does batman really need 200 seconds (PURGE_TIMEOUT) to +switch the route? + +**A:** Batman switches the route as soon as it learns about a better +path towards a destination which can take a fraction of a second up to +several seconds very much depending on the settings and situation. + +When no more new originator messages are sent by a node (because it +died), no more routing updates regarding this node are exchanged. Batman +will not immediately delete this node from its database because the +connection could just have a temporary problem and might recover. Only +after a timeout period of (currently) 200 seconds the node is removed +entirely from batman's internal database. It does not hurt to give the +node a little extra time to recover from a connection loss as it speeds +up the resume process. All routes using this "lost" node as intermediate +hop will have changed towards another path in the meantime and are of no +concern. + +.. _batman-adv-faq-batman-advanced-questions: + +B.A.T.M.A.N. Advanced Questions +------------------------------- + +What can B.A.T.M.A.N. Advanced do? And can't do? +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +**Q:** What offers batman-adv? And what are the 'limitations'? + +**A:** The batman-adv kernel module can only be used to route the +packages within a mesh network, it only simulates OSI layer 2 (data +link layer). It does that as fast as possible and in a smart way. Just +like a switch. + +Batman has no security implemented. Also assigning IP addresses to the +node(s) is not Batman's task. +You may want to use underlying security mechanisms, like: IBSS RSN. + +Read more about :doc:`BATMAN <Wiki>`. + +Can batman-adv run on interfaces in AP / Station / etc mode ? +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +**Q:** Can BATMAN advanced run on interfaces in AP / Station mode? + +**A:** Yes, because batman-adv doesn't know anything about stuff below +the ethernet interface. So you could also use it over layer 2 ethernet +tunnels, wifi ap, wifi sta, wifi adhoc, ethernet or even write a +virtual interface which prints everything on paper and scans the paper +on the remote machine (but you should be fast or increase the ogm +interval). + +How can I connect non-mesh clients to my batman-adv network ? +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +**Q:** How can I connect non-mesh clients to batman-adv network? + +**A:** The :doc:`batman-adv quick-start-guide </batman-adv/Quick-start-guide>` explains how to bridge your standard AP / Ethernet +interfaces with bat0 which can be problematic if you only possess one +WiFi card. In these cases it might be desirable to run adhoc mode and +AP mode at the same time. Fortunately, some WiFi chips / drivers +support a so-called "multi VAP" (virtual AP) or "multi SSID" mode to +have multiple WiFi networks on the same WiFi interface. + +How big networks does batman-adv support? +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +**Q:** How big networks (maximum nodes) does batman-adv support? + +**A:** That is a good question. It is not possible to give an exact +answer, but there are several parameters limiting the number of nodes +in your network: + +#. **Capacity of the wireless network** + Usually, the performance of the wireless network renders unusable if + you add too many nodes (huge delay and low throughput). +#. **Memory footprint** + Each node in the mesh network holds information in memory about every + other node, so little memory might limit the number of nodes. +#. **Protocol overhead** + Each node sends "here-I-am" messages to the entire network at a + regular interval. These messages are aggregated when possible, to + reduce the overhead. + +How do I announce IP subnets using batman-adv? +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +**Q:** Can I setup differnt IP subnets using batman-adv? + +**A:** Batman-adv is a OSI layer 2 routing protocol and it does not +handle IP subnets at all. If you want to do IP subnetting, the +suggestion is to split the mesh network in different sub-meshes (e.g. +different ESSID/BSSID), and run a batman-adv instance in each of them. + +|image0| + +As shown in the picture, the result consists in having multiple meshes +working independently from each other. In particular the border nodes +like C, D and E will participate in more than one mesh network and will +consequently have more than one batman-adv interface (e.g. bat0 and +bat1): each of them assigned an IP belonging to a different subnet. + +At this point the border nodes can run an instance of any dynamic IP +routing protocol (e.g. OSPF or BGP, both implemented in +`Quagga http://www.quagga.net/)`__ which will see each of the +batman-adv mesh network like a single link towards the other (border) +nodes in that network. + +Note that also nodes connected to the Internet like A and B can be +considered border nodes (this is configuration dependant) and can +eventually run the IP routing protocol instance too. + +It is extremely important to do not run any layer3 mesh routing protocol +on top of nodes using batman-adv: this would result in wrong link +quality computation by the overlying protocol which will see the whole +batman-adv network as a single link (even if a path to a node is made up +by multiple hops). + +However the interaction of Quagga with the mesh network will be +"batman-adv-agnostic" since there is no way to exchange information +between the two. The creation of a batman-adv plugin for Quagga could +help in this direction by letting Quagga extract TQ (the metric used by +batman-adv) information to compute link qualities towards other border +nodes in the mesh network. This would avoid the IP routing protocol to +choose bad mesh nodes as next hop in the IP routing. As extracting/using +TQ in other protocols is just an idea/proposal right now, please contact +us if you want to do that. + +Logs not received via trace-cmd? +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + - **Q:** The trace-cmd shows now log messages for batman-adv? ++**Q:** The trace-cmd shows no log messages for batman-adv? + +**A:** You need to compile the batman-adv with logging support. + +* Linux tree + + - go to ``Networking support ---> Networking options ---> B.A.T.M.A.N. Advanced Meshing Protocol`` + and select ``B.A.T.M.A.N. debugging`` and + ``B.A.T.M.A.N. tracing support`` + +* external module + + - compile with make parameter ``CONFIG_BATMAN_ADV_DEBUG=y CONFIG_BATMAN_ADV_TRACING=y`` + +batctl must also be used to set the relevant loglevel + +How to setup B.A.T.M.A.N. so it automatically assign IP addresses? +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +**Q:** How to assign IP addresses automatically? + +**A:** Batman-adv is not responsible for assigning IP addresses. +However, you can use for example a DHCP server. + +What about assigning IP addresses in a decentralized way? +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +**Q:** How to assign IP addresses automatically in a decentralized +way? + +**A:** IPv6 will help you to do this easier by using `Unique local +address https://en.wikipedia.org/wiki/Unique_local_address`__ (ULA). + +What if I want to have a decentralized DNS solution? +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +**Q:** I like to setup a decentralized mesh network and would like to +have a DNS solution. I don't want to use the internet (WWW), but I do +want to have a human readable 'domains' names, just like DNS. What are +the options? + +**A:** Take a look at +`KadNode https://github.com/mwarning/KadNode`__. *Note:* This +software is still in beta. + +.. _batman-adv-faq-batman-advanced-bridge-loop-avoidance-questions: + +B.A.T.M.A.N. Advanced - Bridge Loop Avoidance questions +------------------------------------------------------- + +What is Bridge Loop Avoidance? +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +**Q:** What can you do with BLA? + +**A:** Bridge Loop Avoidance is used to detect and avoid loops due to +multiple batX interfaces. :doc:`Read more... <Bridge-loop-avoidance>` + +Why do we need BLA II if we can just use mesh on Ethernet? +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +Under Discussion -> Features you say "no BATMAN packets on the +backbone". + +**Q:** Why would you want to use the mesh (which never has enough +bandwidth anyway) if you have a fast, reliable backbone link between +some of the nodes (eg. LAN)? +*Or:* Wouldn't it make more sense to get as much done through the +backbone as possible? + +**A:** You can explicitly use batman-adv on the mesh if you want to - +batman-adv allows adding Ethernet interfaces as well. This is a good +idea if you have full control over your LAN. However, there are users +who don't want to see batman-adv ethernet frames (with its special +ethertype 0x4305) on their LAN, because some firewalls recognize it as +malicious traffic. Therefore, one design goal of blaII was to keep +batman-adv packets out of the backbone LAN in the default case. + +What about two meshes interconnected by a LAN? +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +**Q:** Can I setup two meshes and connect them by LAN? *Or:* So, does +this mean that with current blaII, two meshes connected solely by +ethernet backbone (which can't overhear each other OGMs through wifi) +only know which macs are "on the other side of the ethernet backbone" so +as to keep the single broadcast domain united, but are fragmented in +terms of VIS data, gw, TT, and orig table? + +**A:** Yes, there are two separate meshes, and the only stuff which is +supposed to be shared is the users payload traffic. + +What about DHCP server for separate meshes? +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +**Q:** I would like to setup a DHCP server in separate meshes? *Or:* +How can I make two separate meshes use a single DHCP server (using +gw_mode feature) in current blaII design? + +**A:** Each node at the edge to the wired network may announce itself +as a gateway, provided that a DHCP server is available in the LAN (or +any network behind it, e.g. a mesh). From a concept view, a gateway +(or maybe even multiple gateways) in mesh2 will not automatically +announced in mesh1 - this must be configured manually, or let batman +use Ethernet if this is explicitly required. + +B.A.T.M.A.N. Advanced - VLAN questions +-------------------------------------- + +VLAN forwarding doesn't work +~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +**Q**: When I have a bridge which connects an ethernet devices with +bat0, VLAN frames from the ethernet interfaces are not forwarded by +batman-adv. Instead a warning like +``batman_adv: bat0: adding TT local entry xx:xx:xx:xx:xx:xx to non-existent VLAN 23`` +is printed periodically. How is it possible to forward these frames + +**A**: batman-adv since 2014.0.0 is VLAN-aware. It is only able to +forward VLAN frames when it knows about the VLAN. This can either be +done by creating a VLAN device with the correct VID on top of the +batadv (bat0) device: + +:: + + ip link add link bat0 name bat0.23 type vlan id 23 + +Or in case of a VLAN-aware bridge, it is better to add the +VLANs as required to the specific ports: + +:: + + bridge vlan add vid 23 dev bat0 + +.. |image0| image:: quagga_integration.png + diff --cc batmand/Faq.rst index 21b33bf9,00000000..296c981a mode 100644,000000..100644 --- a/batmand/Faq.rst +++ b/batmand/Faq.rst @@@ -1,102 -1,0 +1,102 @@@ +.. SPDX-License-Identifier: GPL-2.0 + +FAQ +=== + +See below a list of batmand (B.A.T.M.A.N. daemon) related questions and +answers. + +If your question is not listed below, please contact us. You can contact - us via IRC: `#batman - channel https://webchat.freenode.net/?channels=batman`__ on - Freenode.org or by sending an e-mail to: b.a.t.m.a.n@lists.open-mesh.org ++us via IRC: `#batadv ++channel https://webirc.hackint.org/#ircs://irc.hackint.org/#batadv`__ on ++hackint.org or by sending an e-mail to: b.a.t.m.a.n@lists.open-mesh.org +(only plain-text). + +Understanding the version and compatibility number +-------------------------------------------------- + +The version number (defined as SOURCE_VERSION in the source)is the one +displayed when launching the batmand in debug mode. It indicates the +state of your code. + +The compatibility number (defined as COMPAT_VERSION in the source) is +transmitted with every broadcasted OGM to guide other batmand instances +receiving this OGM whith the decision about incompatible protocol +versions. + +Why are multiple interfaces problematic? +---------------------------------------- + +The internet (and most network technology today) was designed with the +idea that every interface on a given system has a unique broadcast +adress. When a packet enters a system the kernel has to decide where it +should be routed to. While using the same broadcast adresses on +different interfaces you provoke an undefined situation as this should +not happen (by design) and the result is unpredictable. In that case the +Linux kernel will send all your packages to the first interface (in the +routing table) with that broadcast address. + +A solution to that problem is the usage of the Linux kernel option +"BINDTODEVICE" which allows to specify an outgoing interface for a +packet. Unfortunatly this option is a Linux-only feature (as far as we +know). Therefore you won't be able to use multiple interfaces with the +same broadcast addresses on other operation systems than Linux. + +Log larger amounts of debug messages +------------------------------------ + +First, install netcat on your device. On a OpenWRT based distro you can +try this (packet version may vary): + +:: + + ipkg install http://www.linuxops.net/ipkg/netcat_0.7.1_mipsel.ipk + +Then start batmand and pipe the output into netcat: + +:: + + batmand -d 4 | nc -l -p + +Finally start the netcat client on your logging server and save the +output: + +:: + + nc > batman.log + +If you use a firewall, NAT or any other problematic network setup you +can swap the netcat server position. Beware: Your netcat server has to +be started before you start your netcat client. + +Update many Openwrt based systems +--------------------------------- + +#. Download the update script: `update + script https://downloads.open-mesh.org/batman/useful-scripts-and-tools/update_batman.sh`__ +#. Edit the the variables in the configuration section of the script + to match your needs. +#. Run the script. ;-) + +Note: The HOSTS_TO_UPDATE variable in the script expects SSH host +names which must be configured in your ~/.ssh/config file. + +Tip: Use key based access to authenticate your login request on your +machines to avoid typing your passwords too often. If you use encrypted +keys you can enable the ssh-agent to manage your passwords. + +What is the batgat kernel module good for? +------------------------------------------ + +The batman daemon maintains a tunnel connection to every "batman +internet client". Every packet that goes to the internet or comes back +has to go through this tunnel. As it is a user space tunnel a lot of +copying between user space and kernel land is necessary. Depending on +the number of clients and the CPU power available this might be a +bottleneck. +The batgat kernel module tries to overcome this limitation. Once +loaded the batman daemon will detect its presence automatically on +startup. The daemon will activate the kernel module to let it handle +the tunneling, hence avoiding the expensive copy operations. There is +no difference between the daemon tunneling and the kernel tunneling +other than that. diff --cc open-mesh/IRC.rst index 36ae4cd4,00000000..a9a8ac51 mode 100644,000000..100644 --- a/open-mesh/IRC.rst +++ b/open-mesh/IRC.rst @@@ -1,13 -1,0 +1,13 @@@ +.. SPDX-License-Identifier: GPL-2.0 + +Contact us on IRC +================= + +We are waiting for you on IRC. :) + - - Server: **irc.freenode.org** - - Channel: **#batman** ++* Server: `"**irc.hackint.org** [port 6697, SSL] https://www.hackint.org/connect`__ ++* Channel: `**#batadv** https://webirc.hackint.org/#ircs://irc.hackint.org/#batadv`__ + +Please be patient, we are actually not waiting there all the time. ;) +If you don't have time or have more complex things to talk about, you +should preferably use the :doc:`Mailing List <MailingList>`.