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Subject: Re: pf or ipfw for NAT
To: freebsd-questions@freebsd.org
References: <50dcf18d-f9c3-71c2-abb0-eed8f1b5e192@fjl.co.uk>
 <20210402210356.637a3ed714957fb9c5fdfa3a@sohara.org>
From: Frank Leonhardt <frank2@fjl.co.uk>
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Date: Fri, 2 Apr 2021 21:36:04 +0100
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On 02/04/2021 21:03, Steve O'Hara-Smith wrote:
> On Fri, 2 Apr 2021 20:17:58 +0100
> Frank Leonhardt <freebsd-doc@fjl.co.uk> wrote:
>
>> For longer than I care to remember (FreeBSD 2)  I've implemented a
>> physical asymmetric nat gateway using natd and ipfw. I just do what the
>> user guide says and it works.
> 	Yes it does and that's fine.
>
>> Am I using ipfw/natd for historical reasons? Can I do the same with pf?
> 	Yes you can the relevant line in my pf.conf is:
>
> nat on $ext_if inet from !($ext_if) -> ($ext_if:0)

Thanks Steve. Any idea whether I need to enable the gateway when using 
pf instead?

e.g. sysctl net.inet.ip.forwarding=1

Thanks, Frank.