Delivery Temporarily Suspended Unknown Mail Transport Error Postfix Upd
After a yum update , the error appears only for certain transports. SELinux audit logs ( /var/log/audit/audit.log ) show AVC denied messages.
For remote server flakiness, edit /etc/postfix/main.cf : After a yum update , the error appears
Look for the transport mentioned in your logs. It usually looks something like this: After a yum update