Re: can't add a /24 blackhole route with a /32 loopback

From: Benoit Chesneau <benoitc_at_enki-multimedia.eu>
Date: Wed, 14 Jun 2023 10:40:43 UTC

------- Original Message -------
On Wednesday, June 14th, 2023 at 12:36, Alexander Chernikov <melifaro@FreeBSD.org> wrote:


> > On 14 Jun 2023, at 11:26, Benoit Chesneau benoitc@enki-multimedia.eu wrote:
> > 
> > I found an interresting log in dmesg (see below). Not sure how it can happens.
> > 
> > Could it be related to the usage of bird?
> > 
> > The log:
> > 
> > `[rtsock] fill_blackholeinfo: PID 72835: Unable to find ifa for blackhole/reject nhop [rtsock] fill_blackholeinfo: PID 72837: Unable to find ifa for blackhole/reject nhop [rtsock] fill_blackholeinfo: PID 72838: Unable to find ifa for blackhole/reject nhop [rtsock] fill_blackholeinfo: PID 72847: Unable to find ifa for blackhole/reject nhop [rtsock] fill_blackholeinfo: PID 72854: Unable to find ifa for blackhole/reject nhop [rtsock] fill_blackholeinfo: PID 72860: Unable to find ifa for blackhole/reject nhop`
> 
> Not sure if that’s bird (it shouldn’t be the case), but that’s the reason.
> Every route requires some preferred source interface address by convention, as the stack wants to see some non-NULL value.
> For the blackhole routes, this source address is the first address from lo0 interface.
> In your case, `lo0` doesn’t contain any IPv4 addresses (typically there should be 127.0.0.1 there).
> Is there any reason for not having 127.0.0.1 ?
> 


oh! good catch. When localhost added it works, indeed... Thanks! 

There ws no reason the localhost was not set. I am not sure why it has been not set. I will investigate.

Benoît