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Re: [SLUG] Networking ... explain


On Sunday 11 February 2007 21:57, slug-request@xxxxxxxxxxx wrote:
> I think that unless the ADSL router has a route to the 192.168.0.0
> network, it can't route packets pack from the Internet.
> Its default route is probably something from your ISP. As packets come
> back from the Internet destined for 192.168.0.x, the router only has a
> route to 192.168.5.0 or the default (back to the Internet) to handle it.
>
> I can think of only three options at the mo to fix this:
> 1. Add a route on the ADSL router for the 192.168.0.0 network that uses
> 192.168.5.70 as the gateway
> 2. Open the subnets to be /21 (255.255.248.0) or  /16 to allow the
> subnets to talk without routing. This would seem to defeat the purpose
> of your design though.
> 3. Add NAT to the 192.168.0.1 system so that the 192.168.0.0 network is
> masqueraded as 192.168.5.0. Then the ADSL router doesn't have to deal
> with routing to the 192.168.0.0 network.
>
> Hope I've understood it right.
>
> Mark C.
>
> jam@xxxxxxxxx wrote:
> > Hi
> > if anybody can explain my lack-of-understanding I'd really appreciate it.
> > Thanks
> >
> >
> > -------------------
> > Network 192.168.0.0
> > .
> > 192.168.0.1  Machine
> > 192,168.5.70 One
> > .
> > .
> > 192.168.5.1  ADSL Router
> > .          Internet
> > -------------------
> >
> > Machines in 192.168.0.0 network have default GW 192.168.0.1
> > They can interact (ping etc) with machines in   192.168.5.0 network
> >
> > Machines in 192.168.5.0 metwork have default GW 192.168.5.1
> > They can interact with the 192.168.0.0 machines
> > 192.168.0.0     jupiter.home    255.255.255.0   UG    0      0        0
> > br0 and with the internet
> > default         hawood.home     0.0.0.0         UG    0      0        0
> > br0
> >
> > Of course MachineOne, the GW machine for 192.168.0.0 can see out of
> > 192.168.5.1
> >
> > How do machines in the 192.168.0.0 network get to see the internet out of
> > 192.168.5.1 gateway?
> >
> > [br0 is irrelevant, it could be eth0, it's used by openvpn]
> > James

Mark, crystal clear and easy to understand, thanks very much.

I have elsewhere been warned of the woes of 'double NATing'. I shall try that 
first anyway.

Thanks too to the others who tried to help.
James