On 5/15/07, Zbigniew Baniewski <zb@ispid.com.pl> wrote:
> I'm learning to construct IPFilter-based firewalls, and I've met with
> somewhat strange thing:
>
> following the example http://www.newbie-net.de/anleitung_netbsd_router.html
> I made very similar, simple firewall, just by changing that example
> according to my needs. It was working yesterday, but today in the morning
> I was unable to reach Internet from local network. Something happened(?)
> during the night, although no-one - but me - has access to the machine. When
> I restarted the firewall - all went back to normal. But I don't know, for how
> long.
>
> What can be cause of such "automatic blockade"? It seems, that somewhat the
> routing (or blocking) rules have been changed? But why?
>
> It is:
>
> ipf: IP Filter: v4.1.3 (396)
> Kernel: IP Filter: v4.1.3
>
> ...on NetBSD 2.0 with kernel 2.0.2.
> --
>                                 pozdrawiam / regards
>
>                                                 Zbigniew Baniewski
>


NetBSD 2 is a little old.  Maybe you should try 3 if this is a new install?

Are you sure your rules changed?  On my home router/nat I see this
type of behavior when my ip changes and my routes don't reflect it, or
my rules didn't account for it.

_Matt