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Old 03-10-2004, 09:54 AM   #1
Registered: Oct 2003
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smtp listener (sendmail)

i'm running sendmail on redhat AS2.1
i know that an smtp listener should listen on port 25
when executing : "netstat -a|grep smtp" i found nothing
when i send mail from another host; the mail could not be sent

any help is appreciated
Old 03-13-2004, 06:58 PM   #2
Registered: Feb 2004
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I am having the same problem. When trying to send email from other host, but to an email address of the same domain, it works. For example:

The host is
When sending to , it works. But if i try emailing to , I got this error from outlook express:

The message could not be sent because one of the recipients was rejected by the server. The rejected e-mail address was ''. Subject 'test', Account: '', Server: '', Protocol: SMTP, Server Response: '550 5.7.1 <>... Relaying denied. IP name possibly forged []', Port: 25, Secure(SSL): No, Server Error: 550, Error Number: 0x800CCC79

However, if I log in to using shell, sending email to works fine, and delivered. Anyone know what the problem is?

And how do I make it so the address can be , instead of ?


Using Slackware 9.1, and sendmail 8.12.11
Old 03-13-2004, 09:00 PM   #3
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Registered: Jul 2003
Location: Silicon Valley, USA
Distribution: OpenBSD 4.6, OS X 10.6.2, CentOS 4 & 5
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$ ps -ef | grep -i sendmail
what do you get?

I would highly recommend replacing Sendmail with either Postfix or Qmail. Sendmail has had a terrible history of security flaws, and it's extremely confusing to configure. In most cases, the Postfix binaries can mimic Sendmail and use the same command line options, so any scripts setup to use Sendmail should work fine with Postfix.

The actual problem you're having is due to Sendmail (finally, after decades!) not being an open relay by default. You need to add your IP to the access DB and recompile it (if you really want to continue using Sendmail, that is). On Postfix it's much easier, you just edit the relay host settings in the file and restart the daemon.
Old 03-13-2004, 09:50 PM   #4
Registered: Feb 2004
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I have tried installing postfix, but I faced with so many errors. I used Slackware 9.1 , and did not include sendmail when doing the installation. Then I downloaded postfix, and have problems with db.h . So I installed Berkeley DB (But I want to use MySQL, do I actually need to install Berkeley DB?). THen after this I can do 'make' successfully. But then, when I go to the next step, there is another error. So I decided to stick with sendmail, which already included in the package.


$ ps -ef | grep -i sendmail
root 120 1 0 12:22 ? 00:00:00 sendmail: accepting connections
smmsp 123 1 0 12:22 ? 00:00:00 sendmail: Queue runner@00:25:00 for /var/spool/clientmqueue

That's what I get. And this is what is in my access file:

# /usr/sbin/makemap hash /etc/mail/access.db < /etc/mail/access
localhost RELAY

I added in there, then I recompiled by typing:

# makemap hash /etc/mail/access.db < /etc/mail/access

Then I restarted sendmail (and I even started the computer). Still no luck.. Any other idea why doesnt it work?
Old 03-13-2004, 10:45 PM   #5
Registered: Feb 2004
Posts: 50

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Sorry, I misunderstood the concept for a while. Now, I have added this in the access file:


Now it works. I have another question though, what do I need to do, so that a user in my domain can send email to anywhere? say if someone email address is . Does this mean I have to add (and all others) to access file and recompile it?

And if I relay it to everywhere, does this mean my server can be used by spammer to spam others (if they don't have an access/account)?

One more thing, when I send an email, others see the address as . Is it possible so that they see ? I'm still reading some documentations, but if you do know (or know where I can find the documents), it would be great!



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