PPP Lan Bridge

[Brian Somers]

Hi,

The netmask for the rest of the network should remain the same so that
each machine still thinks it's talking on a /24 (the ppp server is
responding to ARPs so nobody can tell that the ppp server isn't actually
just a multi-homed host).

Only when a packet gets to the ppp server is it actually routed (which
happens because the IP number doesn't match after all -- despite the
ARP table).

I guess the missing bit is that the timeclock machine needs a special
routing table with 192.168.1.234/30 on it's crossed-over ethernet
interface and 192.168.1.233 as the default route, allowing data to
get back to the rest of the /24 subnet.

When you get it all working it'll start to make sense (if it doesn't
already).

On Tue, 22 Mar 2005 14:06:21 -0600, "Chris Tusa at Linisys, LLC" <linisys at gmail.com> wrote:
> Brian,
> 
> Very helpful. Someone on another forum suggsted the possibility of
> adjusting routing using either a routed daemon or setting static
> routes, but it seems that your method seems quicker.  If I segment off
> the PPP side, do I need to change the subnet mask on the rest of the
> network as well?
> 
> (I should know this!)
> 
> -- Chris
> 
> 
> > The issue is that 192.168.1.0/24 machines have to know to route
> > 192.168.2.0/24 stuff through 192.168.1.230, or else the timeclock
> > machine needs some sort of presence on 192.168.1.0/24.
> > 
> > This can be done by allocating a segment of 192.168.1.0/24 to the ppp
> > client and adding ``enable proxyall'' to the ppp server config.
> > 
> > server:
> >   enable proxyall
> >   set ifaddr 192.168.1.230 192.168.1.232/30
> > 
> > client:
> >   set ifaddr 192.168.1.233 192.168.1.230
> > 
> > and then setting the addresses on the crossover cable to 192.168.1.233
> > and 192.168.1.234.
> > 
> > The ``enable proxyall'' bit tells ppp to create proxy arp entries for
> > all of 192.168.1.232/30 (except for .232 and .235), allowing everything
> > else on 192.168.1.0/24 to think it's talking directly to these machines.
> > 
> > --
> > Brian Somers                                          <brian at Awfulhak.org>
> > Don't _EVER_ lose your sense of humour !               <brian at FreeBSD.org>
> > 
> 
> 
> -- 
> Chris Tusa
> linisys at gmail.com
> http://people.linisys.com/ctusa
> 
> Buy books from my Half.com inventory:
> http://half.ebay.com/shops/shops.jsp?seller_id=1691584
> 


-- 
Brian Somers                                          <brian at Awfulhak.org>
Don't _EVER_ lose your sense of humour !               <brian at FreeBSD.org>