How to share internet from WiFi wlan to Ethernet in Ubuntu 16.04

It's easy in windows with lots of software available there but in ubuntu/linux you need to configure wpa_supplicant.conf but through GNOME Network Manager it's easy in Ubuntu also.

• Right click on Network & Select Edit Connections.
• Click on Wired Connection & Select Edit.
• Select IPv4 Settings & choose Shared to other computers. 
• Now, insert your Ethernet cable to device router, laptop, PC else.   

This can be also used to connect multiple routers as Bridge Connections.

Dial-Up--->Router1<---Host1<---Router2<---Host2

To configure router2 as WAN using it's Ethernet PORT4. You need to login to admin pannel & under Advance Settings>>WAN>>You need to check Use Port4 as WAN.

 Read detailed guide here: https://kb.netgear.com/23693/DGN2200V4-Using-LAN-port-4-as-a-WAN-port-for-cable-ISP-connections

To share Internet from Ethernet to wlan just to vice-versa: Under your wifi ssid edit & choose Shared to other computers.

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