arsse Hello I once in a while do (yum -y update) on CentOs. Does it cause any problem like this link? https://www.aapanel.com/forum/d/2236-ols-updating-problem/11
aaPanel_Jose KrzysztofMaciejewski Our server will also be updated regularly After yum update, you need to pay attention to whether the mail server is working. If there is a problem, you can try to restart the postfix service and anti-spam gateway