Bridging wifi to ethernet

[Douglas Phillipson]

Tod Merley wrote:

>  
> Hi Doug!
>  
> Doing a similar thing in the interest of my LUG.
>  
> What follows is for Ubuntu Breezy but the issues are the same:
>  
> I used System>Administration>Networking to establish a static IP 
> (192.168.1.1 <javascript:dl('http://192.168.1.1',1);>) for the laptop 
> ethernet port (and to see that wlan0, the wireless port, was connected 
> to the proper AP and to know it's IP).
> 
> Instructions for setting up the dhcpserver I found at: 
> http://ubuntuguide.org/#dhcpserver
>  
> The iptables in Breezy come unset.  Forwarding accomplished by:
> # iptables:
> # Delete and flush. Default table is "filter". Others like "nat" must be 
> explicitly stated.
> iptables --flush            - Flush all the rules in filter and nat tables
> iptables --table nat --flush
> iptables --delete-chain     - Delete all chains that are not in default 
> filter and nat table
> iptables --table nat --delete-chain
> # Set up IP FORWARDing and Masquerading
> iptables --table nat --append POSTROUTING --out-interface wlan0 -j 
> MASQUERADE
> iptables --append FORWARD --in-interface eth0 -j ACCEPT
> echo 1 > /proc/sys/net/ipv4/ip_forward             - Enables packet 
> forwarding by kernel
> #
> 
> A friend of mine (Paul Edwards) added:
>  
> "The excellent "Firestarter" Gnome firewall software makes this an
> incredibly simple and easy-to-do task with the nice user-friendly GUI.
> "
> Browsing appears normal (laptop or downstream), and use of the "apt-get" 
> "Synaptic" and other tools as well.  However, I had to pull down the 
> Firestarter forwarding/firewall (iptables GUI) to enable the use of an 
> FTP server on the laptop (again, an Ubuntu box - I did get dual boot on 
> FC4 on this box yesterday but have not tried the NAT thing on FC4 there 
> yet) on its ethernet path to another desktop FC4 box on the ethernet 
> wire.  I could ping everywhere and I could browse to the ftp server ( 
> ftp://192.168.1.1 - the laptop ethernet port) from within the laptop but 
> no  one on the wire could do the same.
>  
> Well, at least I am pretty well ready for the next public linux 
> technical session.
>  
> Cheers!
>  
> Tod
> 

Hey thanks all for the great answers.  Give me some time to process all 
this good info and do some testing and I'll post what works for me.

Regards

Doug P