hello i have issue with email bounce back,
i have sendmail server with hostname : s1.moon.com
so let say i sent email to email@example.com, then my datacenter dns cannot resolved it and emaul bounce backed. but bounce backed error will show the email recipient with moon.com at behind the domain. the error like bellow :
----- The following addresses had permanent fatal errors -----
(reason: 553 5.3.5 system config error)
----- Transcript of session follows -----
553 5.3.5 omegaone.com.moon.com. config error: mail loops back to me (MX problem?)
554 5.3.5 Local configuration error
my question is why moon.com appear at behind valid email address ?
where is the conf file i have to fixed the problem ?
any suggestion how to solved ?
sorry for so much question, domain above just for example only and not exist.