Recently I bought 3G Wireless stick. I wanted to shared its internet connection to all my gazettes.
As usual Ubuntu was my friend.
Apparently, it looked as a impossible task.
After a small research, I was successful.
My setup is as follows.
Ubuntu Version used : 14.04 LTS
3G dongle - connected using wireless broadband connection. ( ppp0 Interface )
Ethernet port connected to wireless router. ( eth0 interface )
Ethernet card setup
ip : 192.168.1.25
netmask : 255.255.255.0
gateway : 0.0.0.0 ( Important )
dns : 8.8.8.8
Wireless Router Setup
Network : 192.168.1.1
DHCP : Off (optional )
Step 1: Allow internet sharing On Ubuntu.
From terminal window gave following command to enable packet forwarding for IPv4
sudo nano /etc/sysctl.conf
& uncomment following line & save the file.
net.ipv4.ip_forward = 1
To re-read the changes in systctl.conf file , following command is necessary.
sudo sysctl -p
Step 2: Allow ppp0 interface traffic to interact with the eth0 --
sudo iptables -t nat -A POSTROUTING -s 192.168.1.0/24 -o ppp0 -j MASQUERADE
Step 3 : On other devices, ensure that you give the manual ip and gateway to its wireless connection.
Example : On my Moto G
ip : 192.168.1.30
netmast : 255.255.255.0
gateway : 192.168.1.25 ( very important -- this is a same ip of eth0 of Ubuntu system.
Switch on wifi connection on other devices.
In first go, you will be able connect to Internet for sure.
