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Installation

The Network Address, the Broadcast Address, and the Gateway Address are all

constructed from the machine IP Address and the Netmask. In our example

above, the Netmask of 255.255.255.0  masked  (logical AND) against the IP

Address, 192.64.1.1, gives the Network Address of 192.64.1.0. To obtain the

Broadcast Address, the Netmask is first inverted, to become 0.0.0.255 and a

logical OR performed with the Network Address, yielding a Broadcast Address

of 192.64.1.255 for our example machine. The address of the machine on the

local net that connects to the rest of the Internet is know as the Gateway

Address. These machines are known as routers and typically are the first

(but sometimes the last) address on the local net. This would imply that our

example IP address, 192.64.1.1, is that of a router. In this case the machine

is its own gateway, which is fine depending on your setup.

The last set of information involves Name Servers. When you can ping an IP

Address but can't ping the equivalent Full Name then there is a name server

missing or not configured. If the machine connects to the Internet via an ISP,

then they will provide the name server and will be able to declare the correct

address. If the machine is connected by Ethernet the local system administra 

tor will provide that information. The Debian installation will accept up to 5

name servers for entry into /etc/resolv.conf to be used for name lookup.

The /etc/hosts file from our example above would look like:

127.0.0.1 localhost

192.64.1.1 fred.somewhere.net

While /etc/resolv.conf might look like:

domain somewhere.net

search somewhere.net

nameserver 192.64.1.1

nameserver 199.44.34.2