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nameserver 10.205.41.xx
nameserver 10.204.57.xxx
domain homenet.telecomitalia.it
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E – Install a 3G dongle
This stage is only needed if the system is to be operated away from an existing available network.

Install PPP to allow a data connection to be made:
sudo apt-get install ppp usb-modeswitch libusb-dev

Install sakis3g, which controls the 3G modem:
sudo wget “http://www.sakis3g.org/versions/late...4t/sakis3g.gz”
sudo gunzip sakis3g.gz
sudo chmod +x sakis3g
If this fails because the sakis3g website is unavailable, try this alternative:
sudo wget “Confidentialité- France
sudo gunzip sakis3g.tar.gz
sudo tar -xvf sakis3g.tar
sudo chmod +x sakis3g
sudo apt-get install libusb-dev
sudo ./sakis3g recompile
The last step may take some time with nothing changing on the screen.

Edit/create the sakis3g configuration file:
sudo nano /etc/sakis3g.conf
OTHER=”USBMODEM”
USBMODEM=”12d1:1506"
USBINTERFACE=”0"
APN=”3internet”
These settings are for a Huawei E353 dongle on Three. In the USBMODEM=”12d1:1506? line 12d1:1506 is the dongle`s USB ID which can be found by listing all the currently connected USB devices using:
lsusb
Every device has a different code – the first part represents the manufacturer and the second the product line. Most 3G dongles have two USB IDs – one for the 3G modem and one for the memory card socket. The sakis3g package should ensure that the correct one is selected, but the USBINTERFACE line may help.

Test the configuration by using:
sudo ./sakis3g connect
The 3G dongle light will stop flashing and remain lit once the connection is successfully made, which can take a little while.

The only reliable way of automatically establishing the 3G connection has proved to be to add a line to the Cron table to activate sakis3g every couple of minutes. This also ensures that the connection is automatically remade if the dongle is unplugged/plugged or new credit is added to an expired provider account:
sudo crontab -e
*/2 * * * * root sudo /home/pi/sakis3g connect
This line can be left in place – if the 3G dongle isn`t plugged in then it`s ignored.

Once connected, the RPi will be issued with an IP address by the mobile broadband service. This can be found by using this command:
ifconfig
Look for the inet addr entry in the ppp0 section