diff --git a/docs/user/accessing-nodes.rst b/docs/user/accessing-nodes.rst index 921bc95f..f32ec49c 100644 --- a/docs/user/accessing-nodes.rst +++ b/docs/user/accessing-nodes.rst @@ -1,46 +1,51 @@ Accessing running nodes ======================= -Within the mesh network all Nodes have IPv6 addresses and are treated like regular -computers - with a built-in WLAN device. Once we know the IPv6 address, one can -access the device - to initiate a firmware update, perform various sorts of maintenance -for customized setups, or to just look what is going on when a node does not perform -as expected. +Within the mesh network all nodes have IPv6 addresses and are treated like regular +computers - with a built-in WLAN device. Once we know their IPv6 address, the device +can be accessed. There are various motivations to access a router, e.g. to initiate +a firmware update, perform maintenance for customized setups, to investigate when +a node is not working as expected, to access data from +an external storage deviced, or tap into a sensor network attached to it, and be +it a mere web camera. -**Access** may mean a mere ``ping``/``traceroute`` to determine if a host can be reached. +**Access** in its simplest form may mean a mere ``ping``/``traceroute`` to determine if a host can be reached. To truly enter a machine, one will use SSH. See :doc:`/user/authentication` for information how to set it up. How to find the IPv6 address of a desired node ---------------------------------------------- -The IPv6 addresses of the nodes are static and derived from the MAC addresses. +The IPv6 addresses of the nodes are static and may be derived from their MAC addresses. Consequently, one needs to determine the IPv6 address only once per device. -To find the IPv6 address one can: +To find the IPv6 address one can - * Look at the bottom of the device and find the MAC address there. - * Directly connect via LAN-Cable and use the **next_node** addresses (if configured). - * - There are rules for an automated transcription of MAC addresses into IPv6 - addresses. - You can find one implementation with some description at `ben.akrin.com `_. +* Determine the IPv6 address via the device's MAC address. - The procedure is basically an insertion of ``ff:ef`` in the middle, some bit - swapping and adding ``fe80::`` as prefix. - * - You can find a node address if you know the IPv4 address of a client connected - to it. If you perform a ``batctl traceroute`` to that client from any other Node - in the mesh, the MAC address can be found in the last hub:: + There are rules for an automated transcription of MAC addresses into IPv6 + addresses. You can find an a web service at `ben.akrin.com `_. + The procedure is basically an insertion of ``ff:ef`` in the middle, some bit + swapping and adding ``fe80::`` as prefix. + + To find this physical network address: + + * Look at the bottom of the device and find a label with the MAC address there. + + * You can find a node address if you know the IPv4 address of a client connected + to it. If you perform a ``batctl traceroute`` to that client from any other Node + in the mesh, the MAC address can be found in the last hub:: $ batctl traceroute 10.135.17.193 traceroute to 10.135.17.193 (26:a4:3c:f0:b5:0a), 50 hops max, 20 byte packets 1: 12:fe:ed:3b:3f:cb 22.418 ms 23.008 ms 24.980 ms 2: 26:a4:3c:f0:b5:0a 28.733 ms 26.018 ms 22.403 ms - * - Check response times - the nodes answering first are those connected directly - to the querying host:: + +* Directly connect via LAN-Cable and use the **next_node** addresses (if configured). + +* Check response times - the nodes answering first are those connected directly + to the querying host:: $ ping6 -I bat0 ff02::2 | head -n 5 @@ -50,13 +55,16 @@ To find the IPv6 address one can: 64 bytes from fe80::fa1a:67ff:fe31:69ca: icmp_seq=1 ttl=255 time=27.1 ms (DUP!) 64 bytes from fe80::12fe:edff:feaf:57cc: icmp_seq=1 ttl=255 time=27.5 ms (DUP!) - These addresses are local-link IPv6 addresses and can be contacted directly. + These addresses are local-link IPv6 addresses and can be contacted directly. .. note:: - WLAN and Ethernet are different devices, each with it's own MAC address. + WLAN and Ethernet are different network devices, each with it's own MAC address, + albeit wired up to the same machine. - It is expected that these MAC addresses are not always exactly the same as - the ones seen underneath the device. Only one of either devices is depicted. + These two MAC addresses are commonly not identical. Expect to find only one + of the two devices mentioned on a label. Worse - for the same device, its + reported MAC address may depend on if it is meshing via its WLAN device or + if it is contacting via VPN directly. Contacting the device --------------------- @@ -78,3 +86,4 @@ For SSH, analogously do:: The authenticity of host 'fe80::12fe:edff:feaf:57cc%bat0 (fe80::12fe:edff:feaf:57cc%bat0)' can't be established. RSA key fingerprint is 53:5c:ac:f8:65:74:0b:cb:a4:67:26:3a:f5:65:2f:77. Are you sure you want to continue connecting (yes/no)? +