参考：https://developer.aliyun.com/mirror/saltstack?spm=a2c6h.13651102.0.0.3e221b11yM8nj3
安装镜像源
sudo yum install https://repo.saltstack.com/yum/redhat/salt-repo-latest-2.el7.noarch.rpm
修改为阿里源
sudo sed -i "s/repo.saltstack.com/mirrors.aliyun.com/saltstack/g" /etc/yum.repos.d/salt-latest.repo