(Ted Harding) wrote:
Hi Folks,
I'm gong to try a simpler and more general version of my query.
Three machine, A, B and C.
All 3 on one LAN with coax cable linking their NICs. This LAN is on net 192.168.0.*
In addition, C has an ADSL modem/router on a second NIC, connected with RH45 cable. This 2nd NIC is on bet 192.168.1.*
A and B have a default route to C. This clearly works in each case as verified by performance when C is simply used as a phone-modem dialup (i.e. without ADSL): C, and also A and B through C, can all access the outside world.
With ADSL on C, C has a default route to the IP address of the router. With the ADSL synced to the line, this also works, but from within C alone, as verified by access to the Web.
However, now A and B cannot route out through C, despite the fact that the default routes A->C and B->C are good, and the default route C->Web is good.
'traceroute' to the router's IP from A or B gets an immediate good response from C, but then goes into asterisk mode. 'traceroute -d' returns "network unreachable". So packets are reaching C.
Ted,
It sounds like your router doesn't know how to get to A or B - it is almost certainly receiving the packets but doesn't know how to route to 192.168.0.0/24 (yes, this is the same as 192.168.0.* in answer to an earlier post) hence it is sending its replies out over its default route - that is to your ISP.
You have two options.
* the quickest fix would be to add a static route in your ADSL router/modem, so that it can route back to 192.168.0.0/24 via machine C * otherwise, you can install IPTables and use C to do NAT translation (this will mean that the connections from A or B will look as though they come from C to the router)
Hope this helps,
Jim