bridge eth1 to eth0?

Matt Price matt.price at
Fri Dec 29 20:52:15 UTC 2006


for stupid reasons I need to install via netboot on a compaq tablet
(hoping this will work, it's my last shot!).  I have an ubuntu desktop
with two ethernet cards, eth0 & eth1, and have set up dhcp & tftp on
eth1 as documented in various places on the web, e.g. here:

this works fine to a point.  I have the ubuntu edgy netboot images
in /var/lib/tftpboot, my tablet starts up with pxe, finding the images,
and is ready to install but cannot find the broader internet -- it
doesn't seem to see past the eth1 subnet.  So, probably a simple
question:  how  do I enable the eth1 traffic to bridge across to eth0
and thus access the whole internet?  I guess it has something to do with
ip forwarding or ip masquarading or one of those very scary and arcane
pieces of dark magic.  

I don't want to makethis pre-new year's post too long and am not sure
which pieces of info arethe most relevant but here's
the /etc/network/interfaces on the desktop:

# This file describes the network interfaces available on your system
# and how to activate them. For more information, see interfaces(5).

# The loopback network interface
auto lo
iface lo inet loopback

# The primary network interface
auto eth0
#iface eth0 inet dhcp
iface eth0 inet static

auto eth1 
#iface eth1 inet dhcp
# The second network card with static ip
iface eth1 inet static

I should maybe say that eth0 attaches to a cheap wireless router --
simple but not very flexible.  The router is then in turn attached
through a cable modem to the local cable network.

thanks and please let me know what other info I should provide.  

Matt Price
History Dept
University of Toronto
matt.price at
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