Http:// [Errno 14] curl#6 - "Could not resolve host:; Unknown error" Trying other mirror

Static hostname: localhost.localdomain
Icon name: computer-vm
Chassis: vm
Machine ID: 9528695ded3b446a8bbc5633a6efe409
Boot ID: c003e71c2bbb418e97e16b0590311969
Virtualization: kvm
Operating System: CentOS Linux 7 (Core)
CPE OS Name: cpe:/o:centos:centos:7
Kernel: Linux 3.10.0-862.9.1.el7.x86_64
Architecture: x86-64

Mirror is up and repomd.xml accessible from here. As it already tried for other mirrors the problem points to DNS. Check your server has connection to the Internet and is able to resolve DNS names. It could also be something in between your server and the mirror (proxy…) blocking the connection.