Sendmail -outgoing mail issue from user machines

mn210 · #1 23rd March 2006, 04:50 PM

In our office lan, I have sendmail mailserver(192.168.0.25) running on fedora core and I have opened ports 25 and 143 on Router and smtp and dovecot processes are running on mail server. Now, we want this local mailserver to be used for sending mail out as well as it is receiving mail from outside world fine.
I have tested everything and finally figure out that when TESTING FROM MAILSERVER, I can send mail to outside world but however, when SENDING FROM USER MACHINES, I can only send mail internally and got the relay failure message when sending mail out.
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( From MAIL SERVER )

[sharmam@mail mail]$ telnet mail.example.com 25
Trying 127.0.0.1...
Connected to mail.example.com.
Escape character is '^]'.
220 mail.example.com ESMTP Sendmail 8.12.11/8.12.11; Thu, 23 Mar 2006 10:54:15 -0500
helo mail
250 mail.example.com Hello mail.example.com [127.0.0.1], pleased to meet you
mail from: sharm@example.com
250 2.1.0 sharm@example.com... Sender ok
rcpt to: abc1yahoo.com
250 2.1.5 abc1@yahoo.com... Recipient ok
data
354 Enter mail, end with "." on a line by itself
This is test mail.
.
250 2.0.0 k2NFsFc7004166 Message accepted for delivery
quit
221 2.0.0 mail.example.com closing connection
Connection closed by foreign host.
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Also, I am using the mailserver of ISP as SMART_HOST:
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[root@mail mail]# /usr/sbin/sendmail -bv bobabc@yahoo.com
bobabc@yahoo.com... deliverable: mailer relay, host isp.net, user abc1@yahoo.com
[root@mail mail]# /usr/sbin/sendmail -bv bobabc@hotmail.com
bobabc@hotmail.com... deliverable: mailer relay, host isp.net, user abc2@hotmail.com
[root@mail mail]# /usr/sbin/sendmail -bv sharm
sharm... deliverable: mailer local, user sharm

what changes do I need to make so that data can be sent out from remote machines ??