FreeBSD firewall configuration

[Ian Smith]

In freebsd-questions Digest, Vol 671, Issue 2, Message: 3
On Mon, 10 Apr 2017 21:37:47 +0200 Polytropon <freebsd at edvax.de> wrote:

 > > Can you also help me with the rule to forward incoming trafic to other
 > > interface?
 > 
 > You first need to put
 > 
 > 	net.inet.ip.forwarding=1
 > 
 > into /etc/sysctl.conf and make this change active (read: reboot or

Reboot?  Like Windows? :)

 > manually call "service sysctl restart".
 > 
 > Additionally, add
 > 
 > 	gateway_enable="YES" 
 > 
 > to /etc/rc.conf.

Just a minor niggle .. having gateway_enable="YES" in rc.conf causes 
net.inet.ip.forwarding=1 to be set by /etc/rc.d/routing, so you don't 
need to add it to /etc/sysctl.conf as well - though it won't hurt, 
unless you later wanted to turn it off by updating rc.conf :)

Then just a 'service routing restart' will do the trick.  From which:

        if checkyesno gateway_enable; then
                ropts_init inet
                echo -n ' gateway=YES'
                ${SYSCTL} net.inet.ip.forwarding=1 > /dev/null
        else
                ${SYSCTL} net.inet.ip.forwarding=0 > /dev/null
        fi

cheers, Ian