查看版本

cat /etc/redhat-release

修改源

阿里

mv /etc/yum.repos.d/CentOS-Base.repo /etc/yum.repos.d/CentOS-Base.repo.backup

# 对于 CentOS 7
curl -o /etc/yum.repos.d/CentOS-Base.repo http://mirrors.aliyun.com/repo/Centos-7.repo

# 对于 CentOS 8
curl -o /etc/yum.repos.d/CentOS-Base.repo http://mirrors.aliyun.com/repo/Centos-8.repo

清华

# 对于 CentOS 7
sed -e 's|^mirrorlist=|#mirrorlist=|g' \
    -e 's|^#baseurl=http://mirror.centos.org/centos|baseurl=https://mirrors.tuna.tsinghua.edu.cn/centos|g' \
    -i.bak \
    /etc/yum.repos.d/CentOS-*.repo

# 对于 CentOS 8
sed -e 's|^mirrorlist=|#mirrorlist=|g' \
    -e 's|^#baseurl=http://mirror.centos.org/$contentdir|baseurl=https://mirrors.tuna.tsinghua.edu.cn/centos|g' \
    -i.bak \
    /etc/yum.repos.d/CentOS-*.repo

更新软件源缓存

yum makecache