Hi
Just letting you know that there may be an issue with yum and https for your mirrors.
I haven't tested extensively but
Using CentOS 6.6 x86_64 epel-release-6-8.noarch
yum repolist
Loaded plugins: fastestmirror, priorities, security
Determining fastest mirrors
Error: Cannot retrieve metalink for repository: epel. Please verify its path and try again
wget '
https://mirrors.fedoraproject.org/metalink?repo=epel-6&arch=x86_64&arch=x86_64' works as expected.
I am sure proxy configuration is not the issue as the test system has direct Internet access.