[CentOS] CentOS 4.4 - Email Out

Quoting Tom Brown <tom at ng23.net>:

> I need to set some of our boxes to send mail through our smarthost. In
> the sendmail.mc file i have set the smarthost and rebuilt the
> sendmail.cf file. When i send a mail locally on the box though i get
> this error
>
> Diagnostic-Code: SMTP; 553 5.1.8 <root at localhost.localdomain>... Domain
> of sender address root at localhost.localdomain does not exist
>
> What else do i need to edit as there is something that talks about
> sending from unresolvable domains but this is already allowed i think
>
> FEATURE(`accept_unresolvable_domains')dnl
>
> any ideas ?

The above 553 error was probably generated on your smarthost.

Make sure your host is not called "localhost.localdomain" (in  
/etc/sysconfig/network).  Edit /etc/hosts and make sure your host name  
is not in the 127.0.0.1 line (put it into separate line with your  
host's IP address).