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At this point, you have learned that DHCP is a protocol that allows a server to assign an IP address to a client and DNS is a protocol that takes a domain name and returns an IP address.

Now, we are going to install a program called dnsmasq that provides both a DHCP server and DNS server that will run from your laptop computer.

By installing this server, you will be able to assign, via DHCP, IP addresses to your virtual servers and provide DNS lookup for them.

Begin by installing the dnsmasq package with:

sudo apt-get install dnsmasq


One of the philosophies that Linux has inherited is the idea that we should create small programs that do one thing well. If we want to do more complex tasks, we can combine multiple programs to do more complex things.

One way that programs are combined on the command line is by using the "pipe" character (aka |).

The pipe character takes the output of the first command and sends it as input to the second command.

If you have ever plugged a network cable into a computer, you are familiar with what a physical network interface is like.

Sometimes, it's useful to create "virtual" network interfaces. For example, if you are running multiple virtual servers on a single computer, each virtual server will need a virtual network interface in order to communicate with the network.

You can see a list of all your existing network interfaces with the ip link command:

ip link


Depending on how your computer is configured, you will usually see:

The Internet is made up of many smaller networks, also known as local area networks (LANs) or subnets, that are connected to each other by routers.

When your computer tries to communicate with another computer, it has to make many decisions about where to send the information. One of the first decisions is whether to try to communicate with a computer on the local network, or whether to rely on the router (aka gateway) to forward the information to a computer on a different network.