http://mirrors.163.com/centos/6/os/x86_64/repodata/repomd.xml: [Errno 14] PYCURL ERROR 5 - "Couldn't resolve proxy 'proxy.yoyodyne.com'"
Trying other mirror.
Error: Cannot retrieve repository metadata (repomd.xml) for repository: base. Please verify its path and try again
修改~/.bashrc,删除代理设置,断开ssh重新连接再yum成功。