This is what I've learned lately about telling a new ubuntu installation
how to find the Internet.  The notes here are for (x)ubuntu, since that's
what's on the CD that I got recently.

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2014-7-24 Setting up an interface

Edit /etc/network/interfaces

The current route gadget uses the internal "LAN" address  10.0.1.1,  and  the
entry that works here is:

auto lo
iface lo inet loopback

auto eth1
	iface eth1 inet static
	address 10.0.1.42
	netmask 255.255.0.0
	gateway 10.0.1.1
	dns-nameservers 207.172.3.8 207.172.3.9

This gives the ubuntu the address 10.0.1.42, and of  course  the  42  can  be
anything  from  2  to  254.   You  can use 255.0.0.0 or 255.255.255.0 for the
netmask, depending on how big your local network is.  It's not clear  whether
the gateway address is actually needed; there are conflicting claims about it
online.  The dns-nameservers are at RCN; you'll have to get  these  addresses
from your ISP.  And note that the list is separated by spaces, not commas.

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