netdev - Re: Stateless NAT rule and packets disappearing after postrouting hook *solved*

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Message-ID: <64d3bbc1-0cb2-f4f3-0275-8c8c8ef4bd07@gogi.tv>
Date:   Sat, 21 May 2022 16:59:26 +0200
From:   Daniel Haid <d.haid@...i.tv>
To:     netdev@...r.kernel.org
Subject: Re: Stateless NAT rule and packets disappearing after postrouting
 hook *solved*

> This looks all very mysterious to me. How can I find out what is going
> on?

I found the problem: If I add 10.0.0.1 to *any* interface, then
the kernel will put that address as source into its ARP requests
and somehow my ISP will not allow that. Consequently the default
route does not work.

On the other hand, of only 127.0.0.1 is configured, then the
kernel sees this as having no address at all. I think it will
then send ARP requests with source 0.0.0.0 or something like
that, and then the link to the ISP does work.

So after all, the problem was not actually related to the kernel,
sorry everyone.

D.H.