Re: [RFC PATCH] ipv6: add option to explicitly enable reachability test

From: Eric Dumazet
Date: Tue Mar 28 2023 - 13:54:36 EST


On Tue, Mar 28, 2023 at 5:39 PM Stefan Agner <stefan@xxxxxxxx> wrote:
>
> Systems which act as host as well as router might prefer the host
> behavior. Currently the kernel does not allow to use IPv6 forwarding
> globally and at the same time use route reachability probing.
>
> Add a compile time flag to enable route reachability probe in any
> case.
>
> Signed-off-by: Stefan Agner <stefan@xxxxxxxx>
> ---
> My use case is a OpenThread device which at the same time can also act as a
> client communicating with Thread devices. Thread Border routers use the Route
> Information mechanism to publish routes with a lifetime of up to 1800s. If
> one of the Thread Border router goes offline, the lack of reachability probing
> currenlty leads to outages of up to 30 minutes.
>
> Not sure if the chosen method is acceptable. Maybe a runtime flag is preferred?

I guess so. Because distros would have to choose a compile option.

Not a new sysfs, only an IFLA_INET6_REACHABILITY_PROBE ?

Thanks.