[Linux-aus] Sendmail configuration

[David Newall]

Deepan wrote:
> mails from my server are sent as
> email at localhost.localdomain. How do I change this
> to a valid domain name ? We only own a public IP.
> we dont really have a domain name, is it possible
> to use IP ? 

The domain name is defined by the "j" macro in sendmail.cf.  Look for a
line that includes "Dj".  If you have a fixed IP address then there
should be a name that maps to it.  You can find out what that name is
using the host command (e.g. host 1.2.3.4).  If there is no
reverse-mapping for that address, ask your ISP to insert one. 
Alternatively, you can use one of the dynamic DNS providers (e.g.
dyndns.com); this also works with a dynamic IP address.  Probably best
of all, if you don't have a domain name, is to forward your outgoing
mail to your ISP's mail relay; they're sure to have one for this purpose.