Now we have CentOS 7 minimal installed and the IP configured, first thing we want to do is upgrade ( update + enable obsoletes processing during updates)

yum update && yum upgrade

If you find the prompt for  ‘Do you want to install those blah blah’ annoying, do this:

yum -y update && yum -y upgrade

It is however always a good idea to check and see what is actually getting updated.

Next we want to install telnet:

yum install telnet -y