Download
Images can be downloaded from a location near you.
You can download ISOs from:
http://releases.ubuntu.com/14.04.3/ (Ubuntu Desktop and Server)
http://cloud-images.ubuntu.com/releases/14.04.3/release/ (Ubuntu Cloud Server)
http://cdimage.ubuntu.com/netboot/14.04.3/ (Ubuntu Netboot)
http://cdimage.ubuntu.com/ubuntu-core/releases/14.04.3/release/ (Ubuntu Core)
http://cdimage.ubuntu.com/edubuntu/releases/14.04.3/release/ (Edubuntu DVD)
http://cdimage.ubuntu.com/kubuntu/releases/14.04.3/release/ (Kubuntu)
http://cdimage.ubuntu.com/lubuntu/releases/14.04.3/release/ (Lubuntu)
http://cdimage.ubuntu.com/ubuntustudio/releases/14.04.3/release/ (Ubuntu Studio)
http://cdimage.ubuntu.com/ubuntu-gnome/releases/14.04.3/release/ (Ubuntu GNOME)
http://cdimage.ubuntu.com/ubuntukylin/releases/14.04.3/release/ (UbuntuKylin)
http://cdimage.ubuntu.com/xubuntu/releases/14.04.3/release/ (Xubuntu)
http://cdimage.ubuntu.com/mythbuntu/releases/14.04.3/release/ (Mythbuntu)
_ Centos mirros
http://ftp.tu-chemnitz.de/pub/linux/centos/7/
http://mirror.cisp.com/CentOS/7/
https://www.howtoforge.com/creating_a_local_yum_repository_centos
https://wiki.ubuntuusers.de/apt-mirror/
http://192.168.22.19/ubuntu/mirror/us.archive.ubuntu.com/ubuntu/dists/xenial/