docs: gluon-radv-filterd: enhance documentation with example (#1900)

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Ruben Barkow-Kuder 2020-01-12 17:36:02 +01:00 committed by Andreas Ziegler
parent fbb59cfd60
commit 7220c59661

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@ -13,29 +13,32 @@ Selected router
The router selection mechanism is independent from the batman-adv gateway mode. The router selection mechanism is independent from the batman-adv gateway mode.
In contrast, the device originating the router advertisement could be any router In contrast, the device originating the router advertisement could be any router
or client connected to the mesh, as radv-filterd captures all router or client connected to the mesh, as radv-filterd captures all router
advertisements originating from it. All nodes announcing router advertisement advertisements originating from it. All nodes announcing router advertisement
**with** a default lifetime greater than 0 are being considered as candidates. **with** a default lifetime greater than 0 are being considered as candidates.
In case a router is not a batman-adv originator itself, its TQ is defined by In case a router is not a batman-adv originator itself, its TQ is defined by
the originator it is connected to. This lookup uses the batman-adv global the originator it is connected to. This lookup uses the batman-adv global
translation table. translation table.
Initially the router is the selected by choosing the candidate with the Initially the router is selected by choosing the candidate with the strongest
strongest TQ. When another candidate can provide a better TQ metric it is not TQ. When another candidate can provide a better TQ metric, that outperforms the
picked up as the selected router until it will outperform the currently currently selected router by X metric units, it will be picked as the new
selected router by X metric units. The hysteresis threshold is configurable selected router. The hysteresis threshold is configurable and prevents excessive
and prevents excessive flapping of the gateway. flapping of the gateway.
"Local" routers Local routers
--------------- -------------
The package has functionality to select "local" routers, i.e. those connected Local routers (i.e. local internet gateways connected to some nodes) that are
via cable or WLAN instead of via the mesh (technically: appearing in the connected to the client interface via cable or WLAN instead of via the mesh
``transtable_local``), a fake TQ of 512 so that they are always preferred. (technically: appearing in the transtable_local) are taken into account with a
However, if used together with the :doc:`gluon-ebtables-filter-ra-dhcp` fake TQ of 512, so that they are always preferred.
package, these router advertisements are filtered anyway and reach neither the
node nor any other client. You currently have to disable the package or insert Be aware of problems if you plan to use local routers together with the
custom ebtables rules in order to use local routers. :doc:`gluon-ebtables-filter-ra-dhcp` package. These router advertisements are
filtered anyway and reach neither the node nor any other client. Therefore the
use of local routers is not possible as long as the package
``gluon-radv-filterd`` is used.
respondd module respondd module
--------------- ---------------