1.修改Yum源的优先级
yum install yum-plugin-priorities.noarch
2. 启用插件
cat /etc/yum/pluginconf.d/priorities.conf
[main]
enabled = 1
3. 修改本地Yum源优先使用
cat CentOS-Media.repo
[c7-media]
name=CentOS-$releasever - Media
baseurl=file:///media/cdrom/
gpgcheck=0
enabled=1
priority=1
#priority 数字越小优先级越高