Need I have vagrant for installation edx platform on Ubuntu 12.04 for getting through AWS step

I try to install edx platform on ubuntu 12.04 by this tutorial http://ift.tt/1iW2CoW. I don't use Vagrant but on step [aws | update the ssh motd on Ubuntu] I've got error fatal: [localhost] => error while evaluating conditional: vagrant_home_dir.stat.exists == false. It is strange, because tutorial helps to install edx without vagrant. Why do I get errors about not existing vagrant?

This section, I mean aws, goes after certs. Take a look there http://ift.tt/1Qxkqcd. So... I'm not sure what will be installed by this, but it seems it related to Amazon Web Services. After a little search information about AWS and edx, I've got, that edx can be installed on AWS. But I install edx on my VPS, and it confused me more. Maybe I don't need get through this step. Maybe I don't understand something yet.

Sorry if my english is not clear. Thanks.