[root@localhost ~]# vi /etc/yum

[root@localhost yum]# yum install yum-cron -y

[root@localhost yum]# ls

fssnap.d  pluginconf.d  protected.d  vars  version-groups.conf  yum-cron.conf  yum-cron-hourly.conf

[root@localhost yum]# vi yum-cron.conf

开启自动更新

[root@localhost ~]# systemctl start crond

[root@localhost ~]# yum -y install cronie

[root@localhost ~]# yum -y install yum-cron

[root@localhost ~]# systemctl start yum-cron

关闭自动更新

[root@localhost ~]# gedit /etc/yum/yum-cron.conf

update_messages = no

download_updates = no