[PATCH] wireguard: Use babel type wired for wireguard babel peers.

[Johannes Kimmel]

Hi,

nach unserem aktuellen Kenntnisstand von babeld eine sinnvolle Änderung. 
Konnte auch schon sinnlos oszillierende Routen beobachten und meine 
Geräte sind deswegen schon länger auf wired gestellt.

Reviewed-by: Johannes Kimmel <fff at bareminimum.eu>

On 14.06.20 13:17, Fabian Bläse wrote:
> The babel interface type 'tunnel' has some disadvantageous properties for
> our network.
>
> First, babel tries to evaluate the tunnel performance using the rtt. However,
> this makes the network quite unstable, as rtt might fluctuate a lot, especially
> on less reliable connections (e.g. LTE). Instead of fully falling back to an alternate
> route, this rtt evaluation leads to a lot of flapping routes. Additionally, rtt
> evaluation changes the metric of routes quite often, which leads to many unnessessary
> babel messages in our network.
>
> Also, babeld disables split-horizon processing on 'tunnel' interfaces per default.
> However, split-horizon processing can be done in our point-to-point tunnel setup without
> any issues and has the advantage of significantly reduced babel messages on a link with
> many uplink routes.
>
> Therefore, wireguard babel peers now use the interface type 'wired'.
>
> Signed-off-by: Fabian Bläse <fabian at blaese.de>
> ---
>   src/packages/fff/fff-wireguard/files/etc/gateway.d/50-wireguard | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/src/packages/fff/fff-wireguard/files/etc/gateway.d/50-wireguard b/src/packages/fff/fff-wireguard/files/etc/gateway.d/50-wireguard
> index 69a3d74..d95d522 100644
> --- a/src/packages/fff/fff-wireguard/files/etc/gateway.d/50-wireguard
> +++ b/src/packages/fff/fff-wireguard/files/etc/gateway.d/50-wireguard
> @@ -126,7 +126,7 @@ configure() {
>   		babel_add_iifrules "$prefixname" || { echo "ERROR: Could not add iif-rules for wgpeer $name"; exit 1; }
>   
>   		# add babel interface
> -		babel_add_interface "$prefixname" "$prefixname" 'tunnel' "$rxcost" || { echo "ERROR: Could not add babeld interface for wgpeer $name"; exit 1; }
> +		babel_add_interface "$prefixname" "$prefixname" 'wired' "$rxcost" || { echo "ERROR: Could not add babeld interface for wgpeer $name"; exit 1; }
>   	}
>   
>   	config_load gateway