Sendmail masquerade outgoing email domain.
If you just need an outgoing email from web server use sendmail. But what is masquerading? With the help of masquerading your outgoing email appers from user@example.com instead of realunixuser@server01.example.com. This will also hide your internal user name or host name from rest of the world. So this feature rewrites the hostname in the address of outgoing mail. This is also used when you have centralized mail server i.e. mail hub. Sendmail masquerading configuration Open your sendmail config file /etc/mail/sendmail.mc: # vi /etc/mail/sendmail.mc Append/add/modify the lines as follows: MASQUERADE_AS(example.com)dnl FEATURE(masquerade_envelope)dnl FEATURE(masquerade_entire_domain)dnl MASQUERADE_DOMAIN(example.com)dnl Save and close the file. Replace domain name example.com with your actual domain name. Update and restat sendmail server: # m4 /etc/mail/sendmail.mc > /etc/mail/sendmail.cf # /etc/init.d/sendmail restart