[Gllug] Best practice: Multiple sub-netting/NAT

DL Neil GLLUG at getaroundtoit.co.uk
Fri Jul 27 15:45:07 UTC 2007


Learning Networking in Linux...

I have a Freecom FSG-3 "Storage Gateway" (see earlier msg) which is  
configured as a router, but because it does not handle PPPoA I have to  
have a separate Linksys AM-200 DSL modem to access my UK broadband  
service.

The way things were put together in (the usual?) 'need it yesterday'  
rush, there are effectively two sub-nets: the modem subnet  
(mdm.sub.net.0) and my home-office LAN/local subnet (my.sub.net.0). I  
identified the modem as mdm.sub.net.1 (with the Internet-facing side  
being set by the ISP), and defined the router's respective interfaces  
as mdm.sub.net.2 and my.sub.net.3

NB rather than the perhaps usual my.sub.net.1 definition a la Linksys,  
the ....3 helped my psychology/avoid errors. Hey it works!

Would it be better practice to configure these both in a single  
sub-net instead of the separate sub-nets used at present? eg to run  
the modem as my.sub.net.1 and the router's WAN/modem-facing interface  
as my.sub.net.2 (and leave the router's LAN interface as is)
To what advantage?
In which case what would the LAN-wide sub-net mask become?

Regards,
=dn


-- 
Gllug mailing list  -  Gllug at gllug.org.uk
http://lists.gllug.org.uk/mailman/listinfo/gllug




More information about the GLLUG mailing list