Les Mikesell wrote: > Mail isn't supposed to be rejected for this, but some places probably > do. A more correct approach is to have one name with the A record and > the matching ptr and make all of the other names CNAMEs. > no, no, no! CNAMES are discouraged as they create additional work for everyone else's DNS servers. the only time its proper to use a CNAME is when you are referencing a host on someone else's network who's addressing and management is beyond your control and you won't get notifications if its changing. for email, all the various domains should have MX records with the mail server's "true" name.