通过yum安装ssh执行命令: yun install openssh openssh-server openssh-clients 会报错: Failed to download metadata for repo 'AppStream' 各种尝试,折腾出了另一个错: Repository base is listed more than once in the configuration 意思是仓库配置重复,于是查看配置文件: cd /etc/yum.repos.d 发现有好多配置文件,估计是配置重复导致的,于是先把所有配置文件打个包,以备恢复。 zip centos8-repo.