There is a number of other problems that could prevent your network connection from functioning but the above are the most common ones. You should be able to go through the troubleshooting process pretty quickly. Setting up the network in this course is never a primary task, but it's almost always a prerequisite for anything else we're going to do. You can't have a working web server (or any other kind of server) if you don't have a working network connection.
ssh & ssh == SSH Server == The default (and often the only) way to administer a linux server is via SSH. Even in your case where you have a direct console to all your VM screens you may find it helpful to connect to your virtual machines using SSH (if nothing else - you can resize the terminal window). The SSH server should be installed and running in your VMs. If it's not installed - you can install '''openssh-server''' using yum. Whether it is running or not - you should practice the following commands to make sure you know how to use them, you'll need them for nearly every topic this semester: * '''systemctl start/stop'''* '''systemctl enable/disable'''* '''systemctl status''' == SSH Keys == Using the magic of public key cryptography you can SSH to a linux machine without using a password. This topic is crucial - not only for this course but in the industry, SSH keysare used everywhere that linux servers are used. Here's a great diagram from [http://sebastien.saunier.me/blog/2015/05/10/github-public-key-authentication.html Sébastien Saunier's blog] that's a great simple illustration of how SSH key authentication works: [[Image:ssh_connection_explained.png|800px]] == rsync & cron==