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Date: Thu, 27 Oct 2005 09:43:53 -0500
From: Dan Nelson <dnelson@allantgroup.com>
To: Yance Kowara <yance_kowara@yahoo.com>
Message-ID: <20051027144353.GA5142@dan.emsphone.com>
References: <20051027142007.24881.qmail@web30312.mail.mud.yahoo.com>
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Cc: freebsd-questions@freebsd.org
Subject: Re: packet forwarding
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In the last episode (Oct 27), Yance Kowara said:
> What's the difference between 
> 
> gateway_enable="YES" in /etc/rc.conf
> 
> and
> 
> net.inet.ip.forwarding=1 in /etc/sysctl.conf

>From /etc/rc.d/routing:

        case ${gateway_enable} in
        [Yy][Ee][Ss])
                echo -n ' IP gateway=YES'
                sysctl net.inet.ip.forwarding=1 >/dev/null
                ;;
        esac

So the answer is: nothing, except that adding the line to sysctl.conf
enables packet forwarding before interfaces are configured and other
network variables are set, so you may get spurious "host unreachable"
errors from systems trying to route through the box when it boots up.

-- 
	Dan Nelson
	dnelson@allantgroup.com