yum 源问题：repodata/repomd.xml 404 Not Found

若是在配置是出现

http://dl.fedoraproject.org/pub/epel/6//repodata/repomd.xml: [Errno 14] PYCURL ERROR 22 - "The requested URL returned error: 404 Not Found"

http://repo.percona.com/centos/6/os//repodata/repomd.xml: [Errno 14] PYCURL ERROR 22 - "The requested URL returned error: 404 Not Found"

等问题，请替换相应yum配置文件 /etc/yum.repos.d/extra_repos.repo中的相应连接以下：

http://dl.fedoraproject.org/pub/epel/6/x86_64//

http://repo.percona.com/centos/6/os/x86_64//