site.rst

Site configuration

The site consists of the files site.conf and site.mk. In the first community based values are defined, which both are processed during the build process and runtime. The last is directly included in the make process of Gluon.

Configuration

The site.conf is a lua dictionary with the following defined keys.

hostname_prefix

A string which shall prefix the default hostname of a device.

site_name

The name of your community.

site_code

The code of your community. It is good practice to use the TLD of your community here.

domain_seed

32 bytes of random data, encoded in hexadecimal, used to seed other random values specific to the mesh domain. It must be the same for all nodes of one mesh, but should be different for firmwares that are not supposed to mesh with each other.

The recommended way to generate a value for a new site is:

echo $(hexdump -v -n 32 -e '1/1 "%02x"' </dev/urandom)

prefix4 : optional

The IPv4 Subnet of your community mesh network in CIDR notation, e.g.

prefix4 = '10.111.111.0/18'

Required if next_node.ip4 is set.

prefix6

The IPv6 subnet of your community mesh network, e.g.

prefix6 = 'fdca::ffee:babe:1::/64'

node_prefix6

The ipv6 prefix from which the unique IP-addresses for nodes are selected in babel-based networks. This may overlap with prefix6. e.g.

node_prefix6 = 'fdca::ffee:babe:2::/64'

node_client_prefix6

The ipv6 prefix from which the client-specific IP-address is calculated that is assigned to each node by l3roamd to allow efficient communication when roaming. This is exclusively useful when running a routing mesh protocol like babel. e.g.

node_client_prefix6 = 'fdca::ffee:babe:3::/64'

timezone

The timezone of your community live in, e.g.

-- Europe/Berlin
timezone = 'CET-1CEST,M3.5.0,M10.5.0/3'

ntp_server

List of NTP servers available in your community or used by your community, e.g.:

ntp_servers = {'1.ntp.services.ffac','2.ntp.services.ffac'}

This NTP servers must be reachable via IPv6 from the nodes. If you don't want to set an IPv6 address explicitly, but use a hostname (which is recommended), see also the :ref:`FAQ <faq-dns>`.

opkg : optional

opkg package manager configuration.

There are two optional fields in the opkg section:

• openwrt overrides the default OpenWrt repository URL. The default URL would correspond to http://downloads.openwrt.org/snapshots/packages/%A and usually doesn't need to be changed when nodes are expected to have IPv6 internet connectivity.
• extra specifies a table of additional repositories (with arbitrary keys)

opkg = {
  openwrt = 'http://opkg.services.ffac/openwrt/snapshots/packages/%A',
  extra = {
    gluon = 'http://opkg.services.ffac/modules/gluon-%GS-%GR/%S',
  },
}

There are various patterns which can be used in the URLs:

• %d is replaced by the OpenWrt distribution name ("openwrt")
• %v is replaced by the OpenWrt version number (e.g. "17.01")
• %S is replaced by the target board (e.g. "ar71xx/generic")
• %A is replaced by the target architecture (e.g. "mips_24kc")
• %GS is replaced by the Gluon site code (as specified in site.conf)
• %GV is replaced by the Gluon version
• %GR is replaced by the Gluon release (as specified in site.mk)

regdom : optional

The wireless regulatory domain responsible for your area, e.g.:

regdom = 'DE'

Setting regdom is mandatory if wifi24 or wifi5 is defined.

wifi24 : optional

WLAN configuration for 2.4 GHz devices. channel must be set to a valid wireless channel for your radio.

There are currently three interface types available. You may choose to configure any subset of them:

• ap creates a master interface where clients may connect
• mesh creates an 802.11s mesh interface with forwarding disabled
• ibss creates an ad-hoc interface

Each interface may be disabled by setting disabled to true. This will only affect new installations. Upgrades will not change the disabled state.

Additionally it is possible to configure the supported_rates and basic_rate of each radio. Both are optional, by default hostapd/driver dictate the rates. If supported_rates is set, basic_rate is required, because basic_rate has to be a subset of supported_rates. Possible values are:

• 6000, 9000, 12000, 18000, 24000, 36000, 48000, 54000 (OFDM)
• 1000, 5500, 11000 (legacy 802.11b, DSSS)

The example below disables legacy 802.11b rates (DSSS) for performance reasons. For backwards compatibility in 802.11, this setting only effects 802.11a/b/g rates. I.e in 802.11n 6 MBit/s is announced all time. In 802.11ac the field is used to derive the length of a packet.

ap requires a single parameter, a string, named ssid which sets the interface's ESSID. This is the WiFi the clients connect to.

mesh requires a single parameter, a string, named id which sets the mesh id, also visible as an open WiFi in some network managers. Usually you don't want users to connect to this mesh-SSID, so use a cryptic id that no one will accidentally mistake for the client WiFi.

ibss requires two parametersr: ssid (a string) and bssid (a MAC). An optional parameter vlan (integer) is supported.

Both mesh and ibss accept an optional mcast_rate (kbit/s) parameter for setting the multicast bitrate. Increasing the default value of 1000 to something like 12000 is recommended.

wifi24 = {
  channel = 11,
  supported_rates = {6000, 9000, 12000, 18000, 24000, 36000, 48000, 54000},
  basic_rate = {6000, 9000, 18000, 36000, 54000},
  ap = {
    ssid = 'alpha-centauri.freifunk.net',
  },
  mesh = {
    id = 'ueH3uXjdp',
    mcast_rate = 12000,
  },
  ibss = {
    ssid = 'ff:ff:ff:ee:ba:be',
    bssid = 'ff:ff:ff:ee:ba:be',
    mcast_rate = 12000,
  },
},

wifi5 : optional

Same as wifi24 but for the 5Ghz radio.

next_node : package

Configuration of the local node feature of Gluon

next_node = {
  name = { 'nextnode.location.community.example.org', 'nextnode', 'nn' },
  ip4 = '10.23.42.1',
  ip6 = 'fdca:ffee:babe:1::1',
  mac = '16:41:95:40:f7:dc'
}

All values of this section are optional. If the IPv4 or IPv6 address is omitted, there will be no IPv4 or IPv6 anycast address. The MAC address defaults to 16:41:95:40:f7:dc; this value usually doesn't need to be changed, but it can be adjusted to match existing deployments that use a different value.

When the nodes' next-node address is used as a DNS resolver by clients (by passing it via DHCP or router advertisements), it may be useful to allow resolving a next-node hostname without referring to an upstream DNS server (e.g. to allow reaching the node using such a hostname via HTTP or SSH in isolated mesh segments). This is possible by providing one or more names in the name field.

mesh

Configuration of general mesh functionality.

To avoid inter-mesh links, Gluon can encapsulate the mesh protocol in VXLAN for Mesh-on-LAN/WAN. It is recommended to set mesh.vxlan to true to enable VXLAN in new setups. Setting it to false disables this encapsulation to allow meshing with other nodes that don't support VXLAN (Gluon 2017.1.x and older). In multi-domain setups, mesh.vxlan is optional and defaults to true.

Gluon generally segments layer-2 meshes so that each node becomes IGMP/MLD querier for its own local clients. This is necessary for reliable multicast snooping. The segmentation is realized by preventing IGMP/MLD queries from passing through the mesh.

By default, not only queries are filtered, but also membership report and leave packets, as they add to the background noise of the mesh. As a consequence, snooping switches outside the mesh that are connected to a Gluon node need to be configured to forward all multicast traffic towards the mesh; this is usually not a problem, as such setups are unusual. If you run a special-purpose mesh that requires membership reports to be working, this filtering can be disabled by setting the optional filter_membership_reports value to false.

In addition, options specific to the batman-adv routing protocol can be set in the batman_adv section:

The optional value gw_sel_class sets the gateway selection class. The default is class 20, which is based on the link quality (TQ) only; class 1 is calculated from both the TQ and the announced bandwidth.

mesh = {
  vxlan = true,
  filter_membership_reports = false,
  batman_adv = {
    gw_sel_class = 1,
  },
}

mesh_vpn

Remote server setup for the mesh VPN.

The enabled option can be set to true to enable the VPN by default. mtu defines the MTU of the VPN interface, determining a proper MTU value is described in the :ref:`FAQ <faq-mtu>`.

By default the public key of a node's VPN daemon is not added to announced respondd data; this prevents malicious ISPs from correlating VPN sessions with specific mesh nodes via public respondd data. If this is of no concern in your threat model, this behaviour can be disabled (and thus announcing the public key be enabled) by setting pubkey_privacy to false. At the moment, this option only affects fastd.

The fastd section configures settings specific to the fastd VPN implementation.

If configurable is set to false or unset, the method list will be replaced on updates with the list from the site configuration. Setting configurable to true will allow the user to add the method null to the beginning of the method list or remove null from it, and make this change survive updates. Setting configurable is necessary for the package gluon-web-mesh-vpn-fastd, which adds a UI for this configuration.

In any case, the null method should always be the first method in the list if it is supported at all. You should only set configurable to true if the configured peers support both the null method and methods with encryption.

You can set syslog_level from verbose (default) to warn to reduce syslog output.

The tunneldigger section is used to define the tunneldigger broker list.

Note: It doesn't make sense to include both fastd and tunneldigger sections in the same configuration file, as only one of the packages gluon-mesh-vpn-fastd and gluon-mesh-vpn-tunneldigger should be installed with the current implementation.

Note: It may be interesting to include the package gluon-iptables-clamp-mss-to-pmtu in the build when using gluon-mesh-babel to work around icmp blackholes on the internet.

mesh_vpn = {
  -- enabled = true,
  mtu = 1312,
  -- pubkey_privacy = true,

  fastd = {
    methods = {'salsa2012+umac'},
    -- configurable = true,
    -- syslog_level = 'warn',
    groups = {
      backbone = {
        -- Limit number of connected peers from this group
        limit = 1,
        peers = {
          peer1 = {
            key = 'XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX',
            -- Having multiple domains prevents SPOF in freifunk.net
            remotes = {
              'ipv4 "vpn1.alpha-centauri.freifunk.net" port 10000',
              'ipv4 "vpn1.alpha-centauri-freifunk.de" port 10000',
            },
          },
          peer2 = {
            key = 'XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX',
            -- You can also omit the ipv4 to allow both connection via ipv4 and ipv6
            remotes = {'"vpn2.alpha-centauri.freifunk.net" port 10000'},
          },
          peer3 = {
            key = 'XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX',
            -- In addition to domains you can also add ip addresses, which provides
            -- resilience in case of dns outages
            remotes = {
              '"vpn3.alpha-centauri.freifunk.net" port 10000',
              '[2001:db8::3:1]:10000',
              '192.0.2.3:10000',
            },
          },
        },
        -- Optional: nested peer groups
        -- groups = {
        --   lowend_backbone = {
        --     limit = 1,
        --     peers = ...
        --   },
        -- },
      },
      -- Optional: additional peer groups, possibly with other limits
      -- peertopeer = {
      --   limit = 10,
      --   peers = { ... },
      -- },
    },
  },

  tunneldigger = {
    brokers = {'vpn1.alpha-centauri.freifunk.net'}
  },

  bandwidth_limit = {
    -- The bandwidth limit can be enabled by default here.
    enabled = false,

    -- Default upload limit (kbit/s).
    egress = 200,

    -- Default download limit (kbit/s).
    ingress = 3000,
  },
}

mesh_on_wan : optional

Enables the mesh on the WAN port (true or false).

mesh_on_wan = true,

mesh_on_lan : optional

Enables the mesh on the LAN port (true or false).

mesh_on_lan = true,

poe_passthrough : optional

Enable PoE passthrough by default on hardware with such a feature.

autoupdater : package

Configuration for the autoupdater feature of Gluon.

The mirrors are checked in random order until the manifest could be downloaded successfully or all mirrors have been tried.

autoupdater = {
  branch = 'stable',
  branches = {
    stable = {
      name = 'stable',
      mirrors = {
        'http://[fdca:ffee:babe:1::fec1]/firmware/stable/sysupgrade/',
        'http://autoupdate.alpha-centauri.freifunk.net/firmware/stable/sysupgrade/',
      },
      -- Number of good signatures required
      good_signatures = 2,
      pubkeys = {
        'XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX', -- someguy
        'XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX', -- someother
      }
    }
  }
}

All configured mirrors must be reachable from the nodes via IPv6. If you don't want to set an IPv6 address explicitly, but use a hostname (which is recommended), see also the :ref:`FAQ <faq-dns>`.

config_mode : optional

Additional configuration for the configuration web interface. All values are optional.

When no hostname is specified, a default hostname based on the hostname_prefix and the node's primary MAC address is assigned. Manually setting a hostname can be enforced by setting hostname.optional to false.

To not prefill the hostname-field in config-mode with the default hostname, set hostname.prefill to false.

By default, no altitude field is shown by the gluon-config-mode-geo-location package. Set geo_location.show_altitude to true if you want the altitude field to be visible.

The geo_location.osm section is only relevant when the gluon-config-mode-geo-location-osm package is used. The center.lon and center.lat values are mandatory in this case and define the default center of the map when no position has been picked yet. The zoom level defaults to 12 in this case. openlayers_url allows to override the base URL of the build/ol.js and css/ol.css files (the default is https://cdn.rawgit.com/openlayers/openlayers.github.io/master/en/v5.2.0).

The remote login page only shows SSH key configuration by default. A password form can be displayed by setting remote_login.show_password_form to true; in this case, remote_login.min_password_length defines the minimum password length.

config_mode = {
  hostname = {
    optional = false,
    prefill = true,
  },
  geo_location = {
    show_altitude = true,
    osm = {
      center = {
        lat = 52.951947558,
        lon = 8.744238281,
      },
      zoom = 13,
      -- openlayers_url = 'http://ffac.example.org/openlayer',
    },
  },
  remote_login = {
    show_password_form = true,
    min_password_length = 10,
  },
},

roles : optional

Optional role definitions. Nodes will announce their role inside the mesh. This will allow in the backend to distinguish between normal, backbone and service nodes or even gateways (if they advertise that role). It is up to the community which roles to define. See the section below as an example. default takes the default role which is set initially. This value should be part of list. If you want node owners to change the role via config mode add the package gluon-web-node-role to site.mk.

The strings to display in the web interface are configured per language in the i18n/en.po, i18n/de.po, etc. files of the site repository using message IDs like gluon-web-node-role:role:node and gluon-web-node-role:role:backbone.

roles = {
  default = 'node',
  list = {
    'node',
    'test',
    'backbone',
    'service',
  },
},

setup_mode : package

Allows skipping setup mode (config mode) at first boot when attribute skip is set to true. This is optional and may be left out.

setup_mode = {
  skip = true,
},

Build configuration

The site.mk is a Makefile which defines various values involved in the build process of Gluon.

GLUON_FEATURES

Defines a list of features to include. The feature list is used to generate the default package set.

GLUON_SITE_PACKAGES

Defines a list of packages which should be installed in addition to the default package set. It is also possible to remove packages from the default set by prepending a minus sign to the package name.

GLUON_RELEASE

The current release version Gluon should use.

GLUON_PRIORITY

The default priority for the generated manifests (see the autoupdater documentation for more information).

GLUON_REGION

Region code to build into images where necessary. Valid values are the empty string, us and eu.

GLUON_LANGS

List of languages (as two-letter-codes) to be included in the web interface. Should always contain en.

GLUON_WLAN_MESH

Setting this to 11s or ibss will enable generation of matching images for devices which don't support both meshing modes, either at all (e.g. ralink and mediatek don't support AP+IBSS) or in the same firmware (ath10k-based 5GHz). Defaults to 11s.

Feature flags

With the addition of more and more features that interact in complex ways, it has become necessary to split certain packages into multiple parts, so it is possible to install just what is needed for a specific usecase. One example is the package gluon-status-page-mesh-batman-adv: There are batman-adv-specific status page components; they should only be installed when both batman-adv and the status page are enabled, making the addition of a specific package for this combination necessary.

With the ongoing modularization, e.g. for the purpose of supporting new routing protocols, specifying all such split packages in site.mk would soon become very cumbersome: In the future, further components like respondd support or languages might be split off as separate packages, leading to entangled package names like gluon-mesh-vpn-fastd-respondd or gluon-status-page-mesh-batman-adv-i18n-de.

For this reason, we have introduced feature flags, which can be specified in the GLUON_FEATURES variable. These flags allow to specify a set of features on a higher level than individual package names.

Most Gluon packages can simply be specified as feature flags by removing the gluon- prefix: The feature flag corresponding to the package gluon-mesh-batman-adv-15 is mesh-batman-adv-15.

The file package/features in the Gluon repository (or features in site feeds) can specify additional rules for deriving package lists from feature flags, e.g. specifying both status-page and either mesh-batman-adv-14 or mesh-batman-adv-15 will automatically select the additional package gluon-status-page-mesh-batman-adv. In the future, selecting the flags mesh-vpn-fastd and respondd might automatically enable the additional package gluon-mesh-vpn-fastd-respondd, and enabling status-page and mesh-batman-adv-15 (or -14) with de in GLUON_LANGS could add the package gluon-status-page-mesh-batman-adv-i18n-de.

In short, it is not necessary anymore to list all the individual packages that are relevant for a firmware; instead, the package list is derived from a list of feature flags using a flexible ruleset defined in the Gluon repo or site package feeds. To some extent, it will even allow us to further modularize existing Gluon packages, without necessitating changes to existing site configurations.

It is still possible to override such automatic rules using GLUON_SITE_PACKAGES (e.g., -gluon-status-page-mesh-batman-adv to remove the automatically added package gluon-status-page-mesh-batman-adv).

For convenience, there are two feature flags that do not directly correspond to a Gluon package:

• web-wizard

  Includes the gluon-config-mode-... base packages (hostname, geolocation and contact info), as well as the gluon-config-mode-autoupdater (when autoupdater is in GLUON_FEATURES), and gluon-config-mode-mesh-vpn (when mesh-vpn-fastd or mesh-vpn-tunneldigger are in GLUON_FEATURES)

• web-advanced

  Includes the gluon-web-... base packages (admin, network, WiFi config), as well as the gluon-web-autoupdater (when autoupdater is in GLUON_FEATURES)

We recommend to use GLUON_SITE_PACKAGES for non-Gluon OpenWrt packages only and completely rely on GLUON_FEATURES for Gluon packages, as it is shown in the example site.mk.

Config mode texts

The community-defined texts in the config mode are configured in PO files in the i18n subdirectory of the site configuration. The message IDs currently defined are:

gluon-config-mode:welcome

Welcome text on the top of the config wizard page.

gluon-config-mode:pubkey

Information about the public VPN key on the reboot page.

gluon-config-mode:novpn

Information shown on the reboot page, if the mesh VPN was not selected.

gluon-config-mode:contact-help

Description for the usage of the contact field

gluon-config-mode:contact-note

Note shown (in small font) below the contact field

gluon-config-mode:hostname-help

Description for the usage of the hostname field

gluon-config-mode:geo-location-help

Description for the usage of the longitude/latitude fields (and altitude, if shown)

gluon-config-mode:altitude-label

Label for the altitude field

gluon-config-mode:reboot

General information shown on the reboot page.

There is a POT file in the site example directory which can be used to create templates for the language files. The command msginit -l en -i ../../docs/site-example/i18n/gluon-site.pot can be used from the i18n directory to create an initial PO file called en.po if the gettext utilities are installed.

Note

An empty msgstr, as is the default after running msginit, leads to the msgid being printed as-is. It does not hide the whole text, as might be expected.

Depending on the context, you might be able to use comments like <!-- empty --> as translations to effectively hide the text.

Site modules

The file modules in the site repository is completely optional and can be used to supply additional package feeds from which packages are built. The git repositories specified here are retrieved in addition to the default feeds when make update it called.

This file's format is very similar to the toplevel modules file of the Gluon tree, with the important different that the list of feeds must be assigned to the variable GLUON_SITE_FEEDS. Multiple feed names must be separated by spaces, for example:

GLUON_SITE_FEEDS='foo bar'

The feed names may only contain alphanumerical characters, underscores and slashes. For each of the feeds, the following variables are used to specify how to update the feed:

PACKAGES_${feed}_REPO

The URL of the git repository to clone (usually git:// or http(s)://)

PACKAGES_${feed}_COMMIT

The commit ID of the repository to use

PACKAGES_${feed}_BRANCH

Optional: The branch of the repository the given commit ID can be found in. Defaults to the default branch of the repository (usually master)

These variables are always all uppercase, so for an entry foo in GLUON_SITE_FEEDS, the corresponding configuration variables would be PACKAGES_FOO_REPO, PACKAGES_FOO_COMMIT and PACKAGES_FOO_BRANCH. Slashes in feed names are replaced by underscores to get valid shell variable identifiers.

Examples

site.mk

site.conf

i18n/en.po

i18n/de.po

modules

site-repos in the wild

This is a non-exhaustive list of site-repos from various communities:

• site-ffa (Altdorf, Landshut & Umgebung)
• site-ffac (Regio Aachen)
• site-ffbs (Braunschweig)
• site-ffhb (Bremen)
• site-ffda (Darmstadt)
• site-ff3l (Dreiländereck)
• site-ffeh (Ehingen)
• site-fffl (Flensburg)
• site-ffgoe (Göttingen)
• site-ffgt-rhw (Guetersloh)
• site-ffhh (Hamburg)
• site-ffho (Hochstift)
• site-ffhgw (Greifswald)
• site-ffka (Karlsruhe)
• site-ffki (Kiel)
• site-fflz (Lausitz)
• site-ffl (Leipzig)
• site-ffhl (Lübeck)
• site-fflg (Lüneburg)
• site-ffmd (Magdeburg)
• site-ffmwu (Mainz, Wiesbaden & Umgebung)
• site-ffmyk (Mayen-Koblenz)
• site-ffmo (Moers)
• site-ffmg (Mönchengladbach)
• site-ffm (München)
• site-ffhmue (Münden)
• site-ffms (Münsterland)
• site-neuss (Neuss)
• site-ffniers (Niersufer)
• site-ffndh (Nordheide)
• site-ffnw (Nordwest)
• site-ffrgb (Regensburg)
• site-ffrn (Rhein-Neckar)
• site-ffruhr (Ruhrgebiet, Multi-Communities)
• site-ffs (Stuttgart)
• site-fftr (Trier)