[K12OSN] Blocked net access

[Robert Arkiletian]

On 1/12/07, Eric Harrison <eharrison at mail.mesd.k12.or.us> wrote:
> David Whitmer wrote:
> > On 1/12/07, Les Mikesell <les at futuresource.com> wrote:
> >>
> >> I think the script and setup tries to automatically determine that you
> >> have a 2-NIC
> >> configuration and only activates NAT for that case.  Having eth0 down
> >> must make
> >> it look like a single NIC setup.
> >>
> >> --
> >>  Les Mikesell
> >>   les at futuresource.com
> >>
> >
> > hmmm...
> >
> > We're running 4 K12LTSP servers at our schools.  On all but one
> > routing has always worked perfectly for any Windows PCs connected to
> > the "internal" subnet.  The server this has never worked on, though,
> > is one where I know for sure I did not have either NIC (it has two)
> > connected during the K12LTSP installation.
> >
> > Perhaps my problem is that, since the NICs weren't connected during
> > the installation and setup, that the setup didn't think it needed to
> > configure & activate NAT?
>
>
> The nat service is pretty simple. If you strip it down, this is all it does:
>
>         PUBLIC_ETHERNET="eth1"
>         iptables -t nat -A POSTROUTING -o $PUBLIC_ETHERNET -j MASQUERADE
>         echo 1 > /proc/sys/net/ipv4/ip_forward
>
>
> It doesn't care if the interface is up or down, what the ip address is,
> etc, etc. The only configurable item is the interface that is nat'd.
>
> If your public interface is on something other than eth1, edit
> /etc/init.d/nat and change the "PUBLIC_ETHERNET=" line.
>

Thanks a bunch guys. I was just about to ask the same question. I am
putting Slax linux on my clients with a dual boot lilo config to
k12ltsp. I must be losing the nat service when I ifdown eth0 then ifup
eth0. I do this when I'm lecturing to disable the net.

-- 
Robert Arkiletian
Eric Hamber Secondary, Vancouver, Canada
Fl_TeacherTool http://www3.telus.net/public/robark/Fl_TeacherTool/
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