Note

You’ll note that the network interface names used on the hosts in this book use the familiar eth (eth0, eth1, and so on) naming convention. While this is still the standard on many versions of Linux, newer versions that run systemd (such as Ubuntu 16.04) now use something called Predictable Network Interface Names (PNIN). With PNIN, the network interface uses more predictable names based on the information about the interface itself. In these cases, the interface names will show up using different names, such as ens1 or ens32. For the sake of making the content in this book easier to understand, I chose to disable PNIN on all of the hosts. If you’re interested in doing the same instructions can be found by doing a web search for ‘Ubuntu disable predictable interface names’. If you chose not to, just know that your interface names will show up differently than mine do in the examples.