Your Local Domain is example.

Do the following steps as:

1.vi /etc/mail/local-host-names

example.com

2.vi /etc/mail/sendmail.mc

dnl # DEAMON_OPTIONS(`Port=smtp,Addr=127.0.0.1,Name=MTA`)dnl

MASQUERADE_AS(`example.com')dnl

define(`SMART_HOST',`smtp.abc.com')

3.m4 /etc/mail/sendmail.mc >/etc/mail/sendmail.cf

4.vi /etc/mail/virtusertable

info@example.comadmin@example.com

5.vi /etc/mail/access

192.168.0RELAY

/etc/mail/local-host-names file contains the aliases to hostname. Mail server program reads the /etc/mail/sendmail.cf. To change the configuration on mail server, we should edit the /etc/mail/sendmail.mc file and should generate the sendmail.cf using m4 command.

By default sendmail server allows to connect to local host only. So we should edit the /etc/mail/sendmail.mc file to allow connect to other hosts.

By default sendmail server will not forward mail. We should specify on /etc/mail/access to relay or to block mail coming from domain or network or individual email address.

To masquerade the address, MASQUERADE_AS option is in /etc/mail/sendmail.mc. SMART_HOST deliver all local mail locally and outgoing mail through another mail server.

/etc/mail/virtusertable file is used map virtual address to real address.

Eg.

info@example.comuser1@example.com

enquiry@example.comadmin@abc.com