I was going to be testing out a very minimal server, so I chose to install Cent OS 7 minimal version. To my surprise, after installation I noticed that network was not ON by default!
After some searching, I realized that I need to edit /etc/sysconfig/network-scripts/ifcfg-eth0 to read:
Note that you will need to replace eth0 with your network adapter name.
In addition, there is no ifconfig or wget on Cent OS minimal, which I understand. To install these, simply run
# yum install -y net-tools wget