I rebooted the router and my IP changed, I don't have a static one, so now I'm clear. My IP was something like 79.xxxxxx before the reboot. You may want to try to look for it or I'll send it if it will be assigned to me again in the future and it's still banned.
As for CentOS6 and XmrStak, I tried to compile on a VirtualBox VM and it worked flawless with the instructions provided some posts ago, I only had to add some switches in order to disable AMD and NVIDIA since on the server I don't have any gpus so I will only benefit from cpu cores. For the real deal on the real server I have to wait for a sysadmin friend of mine. With the switches the updated instructions are:
sudo yum install centos-release-scl epel-release
sudo yum install cmake3 devtoolset-4-gcc* hwloc-devel libmicrohttpd-devel openssl-devel make
scl enable devtoolset-4 bash
git clone https://github.com/fireice-uk/xmr-stak.git
mkdir xmr-stak/build
cd xmr-stak/build
cmake3 .. -DOpenCL_ENABLE=OFF -DCUDA_ENABLE=OFF
make install