When the mail server transfers messages to ironport the following message:Error transferring to <IRON PORT IP>; SMTP Protocol Returned a Permanent Error 553 #5.1.8 Domain of sender address <xxx@midomain.cl> does not exist
Paul, Thank youIndeed the DNS defined in ironport was not working. There is a way to monitor this service and alarmed when it happens, that , failing the DNS internal emails sent to internet were rejected with the error reported
