Step 1: Back up important files
Red Hat has finally placed sendmail.cf in /etc/mail, where it belongs. To verify the location of your configuration file, type this command:
sendmail -d0.20 -bv | grep sendmail.cf
The default installation outputs this:
Conf file: /etc/mail/sendmail.cf (default for MTA)
Conf file: /etc/mail/sendmail.cf (selected)
Be sure to use this path when generating your new sendmail.cf from sendmail.mc, or no changes will take place. Back up your current sendmail.cf and the m4 file that generated it (probably /etc/mail/sendmail.mc):
cp /etc/mail/sendmail.cf /etc/mail/sendmail.cf~
cp /etc/mail/sendmail.mc /etc/mail/sendmail.mc~
Step 2: Make your certificate
