# yum install sendmail sendmail-cf
# vim /etc/mail/sendmail.mc
DAEMON_OPTIONS(`Port=smtp,Addr=127.0.0.1, Name=MTA')dnl
==> DAEMON_OPTIONS(`Port=smtp,Addr=0.0.0.0, Name=MTA')dnl
# m4 /etc/mail/sendmail.mc /etc/mail/sendmail.cf
[root@steeleye02 mail]# cat /etc/mail/access
Connect:localhost.localdomain RELAY
Connect:localhost RELAY
Connect:127.0.0.1 RELAY
¼öÁ¤==>Connect:0.0.0.0 RELAY
# systemctl restart sendmail