sendmail

[Linda Lux]

My network person is telling me my HP server is showing as an open relay - so my sendmail is being refused. How can I change my server to only sendmail from itself and not acted as an open relay for any server on our network to use.

[A. Clay Stephenson · Accepted solution]

If all you want to do is send mail then sendmail does not have to run as a daemon. Sendmail only needs to run as a daemon if you need it to receive mail.

[Linda Lux]

I am new at this, so explain this further:

[Uday_S_Ankolekar]

stop sendmail process on your hpux server.
You don't have to run this all the time if your server is not meant for receive mails
/sbin/init.d/sendmail stop.

-USA..

[A. Clay Stephenson]

1) Execute /sbin/init.d/sendmail stop
2) Edit /etc/rc.config.d/mailservs and set SENDMAIL_SERVER=0 and save the file.

You should then be able to send mail (internally and externally) just as you always have but no external email will be received.

[Linda Lux]

So if a user on the HPUX sends a confirmation from our application to user@whater.com it will go out to them?

[A. Clay Stephenson]

Now that's an entirely different question. The answer is "yes" is you have sendmail properly configured and "no" otherwise. A very common way to deal with your situation is to designate a smart relay so that all external email processing is haned off to another mail server. Look in the file /etc/mail/sendmail.cf and look for "Smart". The comments will tell you how to set the DS macro.

The difference between running in daemonm mode and what I'll call vanillas mode is that in daemon mode, sendmail is rinning all the time listening for requests from external mail processes. In "vanilla" mode, a new instance of sendmail is spawned with every mail request (from mail, mailx, elm, et al); the new sendmail instance performs its task and then terminates.

[A. Clay Stephenson]

Now that's an entirely different question. The answer is "yes" is you have sendmail properly configured and "no" otherwise. A very common way to deal with your situation is to designate a smart relay so that all external email processing is haned off to another mail server. Look in the file /etc/mail/sendmail.cf and look for "Smart". The comments will tell you how to set the DS macro.

The difference between running in daemonm mode and what I'll call vanilla mode is that in daemon mode, sendmail is rinning all the time listening for requests from external mail processes. In "vanilla" mode, a new instance of sendmail is spawned with every mail request (from mail, mailx, elm, et al); the new sendmail instance performs its task and then terminates.

[Linda Lux]

Which would you recommend doing?
Set the server to 0? and shut sendmail off?
all of the requests to send mail are from users on the HP server.

Linda

[A. Clay Stephenson]

Do it just as I said earlier and in this order:

1) Execute /sbin/init.d/sendmail stop
2) Edit /etc/rc.config.d/mailservs and set SENDMAIL_SERVER=0 and save the file.

Unless SENDMAIL_SERVER=1 initially the /sbin/init.d/sendmail stop will do nothing so leave it at 1 until the sendmail daemon is terminated THEN edit the config file and set it to 0 so that subsequent reboots will not start the daemon.

After doing these steps, do a test such as
echo "This is test mail." | mail user@somewhere.com.

[Sam McKnight]

You might want to look at the O'Reilly books 'Sendmail' and 'Sendmail 8.13 Companion.' They have good explanations of the features of sendmail.