If you want to activate sendmail (SMTP) Server…
/etc/mail/sendmail.mc file
uncomment by adding dnl in front of below line
DAEMON_OPTIONS(`Port=smtp,Addr=127.0.0.1, Name=MTA')dnl </lang> So it becomes <pre lang="none"> dnl DAEMON_OPTIONS(`Port=smtp,Addr=127.0.0.1, Name=MTA')dnl
Now after modifying sendmail.mc, regenerate sendmail.cf
m4 < sendmail.mc > sendmail.cf
restart sendmail
/etc/init.d/sendmail restart
Also edit /etc/hosts.allow
#for allowing connection from local machine only sendmail:localhost 127.0.0.1 localhost.localdomain #or for allowing connection from all around the world -> not safe sendmail:ALL #Make sure add all local host domain in /etc/mail/local-host-names to receive email for those domain
And restart sendmail
/etc/init.d/sendmail restart