Skip site navigation (1)Skip section navigation (2)
Date:      Mon, 29 Jun 2015 12:54:32 +0200
From:      Milan Obuch <freebsd-pf@dino.sk>
To:        Ian FREISLICH <ian.freislich@capeaugusta.com>
Cc:        Daniel Hartmeier <daniel@benzedrine.ch>, freebsd-pf@freebsd.org
Subject:   Re: Large scale NAT with PF - some weird problem
Message-ID:  <20150629125432.7aff9e66@zeta.dino.sk>
In-Reply-To: <E1Z9WW6-000PzF-PO@clue.co.za>
References:  <20150629114506.1cfd6f1b@zeta.dino.sk> <14e119e8fa8.2755.abfb21602af57f30a7457738c46ad3ae@capeaugusta.com> <E1Z6dHz-0000uu-D8@clue.co.za> <E1Z6eVg-0000yz-Ar@clue.co.za> <20150621195753.7b162633@zeta.dino.sk> <E1Z7Ixx-0006K1-5p@clue.co.za> <E1Z7K1Y-0006Ph-ON@clue.co.za> <20150623112331.668395d1@zeta.dino.sk> <20150628100609.635544e0@zeta.dino.sk> <20150629082654.GA22693@insomnia.benzedrine.ch> <20150629105201.7ee24e38@zeta.dino.sk> <20150629092932.GC22693@insomnia.benzedrine.ch> <E1Z9WW6-000PzF-PO@clue.co.za>

next in thread | previous in thread | raw e-mail | index | archive | help
On Mon, 29 Jun 2015 12:42:22 +0200
Ian FREISLICH <ian.freislich@capeaugusta.com> wrote:

> Milan Obuch wrote:
> > On Mon, 29 Jun 2015 11:29:32 +0200
> > Daniel Hartmeier <daniel@benzedrine.ch> wrote:
> > 
> > > On Mon, Jun 29, 2015 at 10:52:01AM +0200, Milan Obuch wrote:
> > > 
> > > > Does this answerred your question fully or something more would
> > > > be usefull?
> > > 
> > > How are you doing ARP?
> > >
> > > You're not assigning every address on x.y.26.0/23 as an alias, are
> > > you?
> > > 
> > > So who answers ARP requests of the upstream router?
> > 
> > There is no ARP on routed address block.
> > 
> > In cisco speak, there is just
> > 
> > ip route x.y.24.0 255.255.252.0 x.y.3.19
> > 
> > statement and that's it. Nothing more. Whole address range from
> > x.y.24.0 to x.y.27.254 is routed here as it should be. For something
> > like this ARP would be really evil solution.
> 
> That's OK, as long as the NAT network is routed to your PF box it
> will work.
>

This was just an explanation, I am sure this is OK, as I have some
network experience already for... well, a ong time.

> The situation you mentioned in a previous message where you see
> lots and lots of NAT states for a single public IP address is what
> I suspected was happening.  When you require more NAT states per
> IP than ephemeral ports you will run into issues because you will
> run out of NAT space.
>

No, there were not much states per problematic IP, maybe just tens of
them for one or couple internal IPs. That's weird.

> If the round-robin works with a smaller pool, then I suspect Glebius
> will be interested.
> 

Well, if he chimes in, I would only welcome that. Currently I am
waiting for any signs of troubles with shrinked pool, if there will be
any.

Milan



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20150629125432.7aff9e66>