CentOS报以下错误：
Invalid configuration value: failovermethod=priority in /etc/yum.repos.d/CentOS-epel.repo; Configuration: OptionBinding with id "failovermethod" does not exist只需要找到出错的文件（/etc/yum.repos.d/CentOS-epel.repo），注释掉failovermethod即可。
[epel]
name=Extra Packages for Enterprise Linux 8 - $basearch
baseurl=http://mirrors.cloud.aliyuncs.com/epel/8/Everything/$basearch
#failovermethod=priority
enabled=1
gpgcheck=0
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-EPEL-8