centos8使用yum安装软件报错

问题1
问题：/etc/yum.repos.d/CentOS-Epel.repo; Configuration: OptionBinding with id "failovermethod" does not exist

解决：

1. 找到对应的repo文件：/etc/yum.repos.d/CentOS-Epel.repo

2. 注释掉failovermethod=priority这一行，即编辑该repo文件，在对应行添加 "#" 注释

问题2
问题："Failed to download metadata for repo 'appstream': Cannot prepare internal mirrorlist: No URLs in mirrorlist"

解决：

cd /etc/yum.repos.d/
sed -i 's/mirrorlist/#mirrorlist/g' /etc/yum.repos.d/CentOS-*
yum update -y

如果上述完成之后，仍报错 ：
Error: Cannot find a valid baseurl for repo: appstream

继续如下操作：
sed -i 's|#baseurl=http://mirror.centos.org|baseurl=http://vault.centos.org|g' /etc/yum.repos.d/CentOS-*

wget -O /etc/yum.repos.d/CentOS-Base.repo https://mirrors.aliyun.com/repo/Centos-vault-8.5.2111.repo

yum clean all

yum makecache

做完上述4部之后，再测试一下
yum update -y