unable to ping through router

trainpic · 08-07-2006, 02:14 PM

I have two networks at my house. One is a linksys wireless router (not the router with the trouble), with a WinXP desktop connected to it that connects to the internet via dialup. The other is a small ethernet downstairs. I recently set up a toshiba laptop with a wireless card and an ethernet card to act as a router between the two networks. The ethernet is only for edubuntu terminal clients. The terminal server is 192.168.1.1, and the laptop's ethernet interface is 192.168.1.2. iptables is enabled, and set to only forward packets with the server's source or destination address, as I don't want anyone messing with the thin clients. the servers default gateway is set to 192.168.1.2. The linksys router is 192.168.0.254, the laptop's wireless card is 192.168.0.3, and the WinXP computer is 192.168.0.1. When I attempt to ping the linksys router or the winxp computer from the server, I get no errors and no replies. I have enabled ip forwarding with

Code:

echo 1 > /proc/sys/net/ipv4/ip_forward

.

acid_kewpie · 08-07-2006, 03:19 PM

sounds like there is no return route. if you are going from one network to another, you're presumably taking the default route out of the local subnet, but as on your destination network the default route won't take you to the source subnet your data is lost. i'd probably suggest that your adsl router would be a good place to add a route back to the source subnet, as this would presumably already be being used as a default route anyway, so will already be being sent the traffic you can't find. just tell this box to send traffic for the source subnet back to the laptop router and it should reappear where you expect it to.

trainpic · 08-08-2006, 07:57 AM

I will try this. Thanks. I never thought (though it makes sense now) that I would have to add the route on both sides. Silly me. :-)

trainpic · 08-08-2006, 08:28 AM

Still doesn't work!! I added the laptops wireless interface IP (192.168.0.3) to the linksys router's routing table as a way to access the 192.168.1.0 network, and I still get no replies on pings.

acid_kewpie · 08-08-2006, 09:04 AM

well this is where you'd use tools like traceroute to see where a packet goes to on the journey between both machines. try from client and server.