LeapFrog Pollux Platform: Internet Access
Summary
There are two methods of accessing the internet from your LeapFrog Pollux Platform device. While both require hooking up to a host PC, you can either using routing, or bridging to make the connection. Either way nets you the same goal. Some differences are Bridging deals with Layer 2 of the OSI model and and allow DHCP broadcasts, while Routing involves Layer 3.
Prerequisites
For the Didj, it requires you Enable Networking
Configuring the Host
In this example, we assume that the host has an ethernet connection on eth0. To check your specific device, run.
On Host
ifconfig
You should see eth[X] and lo, X is the number of your ethernet interface.
As for the IP addresses used, you could use any reasonable ones you want, for this example we'll use.
For this example we establish the following assumptions:
The gateway between the local network and the Internet is 192.168.0.1
The host is connected to the gateway as 192.168.0.116 (assigned by DHCP on eth0)
The host is connected to the Didj as 10.0.0.1 (assigned statically to usb0 on host)
The Didj is connected to the host as 10.0.0.2 (assigned statically to usb0 on Didj)
Configure the host machine's /etc/network/interfaces file as follows:
auto lo
iface lo inet loopback
auto eth0
iface eth0 inet dhcp
auto usb0
iface usb0 inet static
address 10.0.0.1
netmask 255.255.255.0
up route add -net 10.0.0.0 netmask 255.255.255.0 dev usb0
up echo 1 > /proc/sys/net/ipv4/ip_forward
up iptables -P FORWARD ACCEPT
up iptables -A POSTROUTING -t nat -j MASQUERADE -s 10.0.0.2
down route del -net 10.0.0.0 netmask 255.255.255.0
down echo 0 > /proc/sys/net/ipv4/ip_forward
down iptables -t nat -F POSTROUTING
To apply these new settings:
On the Host:
sudo /etc/init.d/networking restart
(of course, rebooting the host will also work)
Configuring the Didj
If you are using a standard Didj configuration and you have not yet done so, rmmod the g_file_storage kernel module and insmod the g_ether/ko module. (see http://elinux.org/Didj_Networking_HOWTO#Installing_g_ether.ko)
With the USB cable connected to your host, configure an IP address on a different subnet from the rest of your LAN
On the Didj:
ifconfig usb0 10.0.0.2 netmask 255.255.255.0
Next, add a route from your Didj to the host (making it the gateway) using the ip address of the host's usb0 device.
On the Didj:
route add default gw 10.0.0.1 usb0
Finally, add nameservers to your Didj's /etc/resolv.conf file (you can add the lines from this example which uses the OpenDNS servers)
nameserver 208.67.222.222 nameserver 208.61.220.220
At this point, your Didj is connected to the outside world - and a ping or a wget to yahoo or google should work.
Todo
Routing packets from the gateway to the Didj.
References
http://wiki.openmoko.org/wiki/USB_Networking
http://wiki.openzaurus.org/HowTos/USB_Networking_Without_Bridging
Acknowledgments
Thanks to losinggeneration for useful input on this!