Sendmail - How can I block this? - I think it is spam.

[virgil66ro]

in /var/log/maillog i have the following message:

Feb  3 13&#58;46&#58;26 1oopis sm-mta&#91;12447&#93;&#58; i13BkQuO012447&#58; <jack@oopis.ro>... User unknown
Feb  3 13&#58;46&#58;27 1oopis sm-mta&#91;12447&#93;&#58; i13BkQuO012447&#58; lost input channel from &#91;82.76.104.39&#93; to MTA after rcpt
Feb  3 13&#58;46&#58;27 1oopis sm-mta&#91;12447&#93;&#58; i13BkQuO012447&#58; from=<maria@natali.cz>, size=0, class=0, nrcpts=0, proto=ESMTP, daemon=MTA, relay=&#91;82.76.104.39&#93;

Feb  3 13&#58;56&#58;12 1oopis sm-mta&#91;12607&#93;&#58; i13Bu9uO012607&#58; ruleset=check_mail, arg1=<mike@gto.net.om>, relay=&#91;82.76.104.39&#93;, reject=553 5.1.8 <mike@gto.net.om>... Domain of sender address mike@gto.net.om does not exist
Feb  3 13&#58;56&#58;12 1oopis sm-mta&#91;12607&#93;&#58; i13Bu9uO012607&#58; from=<mike@gto.net.om>, size=0, class=0, nrcpts=0, proto=ESMTP, daemon=MTA, relay=&#91;82.76.104.39&#93;

Feb  3 14&#58;08&#58;14 1oopis sm-mta&#91;12797&#93;&#58; i13C8EuO012797&#58; <jane@oopis.ro>... User unknown
Feb  3 14&#58;08&#58;14 1oopis sm-mta&#91;12797&#93;&#58; i13C8EuO012797&#58; lost input channel from &#91;82.76.104.39&#93; to MTA after rcpt
Feb  3 14&#58;08&#58;14 1oopis sm-mta&#91;12797&#93;&#58; i13C8EuO012797&#58; from=<brent@asu.ro>, size=0, class=0, nrcpts=0, proto=ESMTP, daemon=MTA, relay=&#91;82.76.104.39&#93;

As you can see, all says that relay=[82.76.104.39].

To protect my server, i put in /etc/mail/access the following line:

82.76.104.39 DISCARD

But, this do not change nothing.

Please HELP!

[Dolda2000]

Don't worry about it - that just shows that sendmail already has detected it and blocked it. Thus, you don't need to do anything more about it.

The reason your solution didn't work was because it tells sendmail to discard the message, which it already had decided to do since it had detected that the message was bogus.

[virgil66ro]

I think that the messages only messages with invalid address are rejected, but what about when the address is valid?

I do not want to relay spam.

Can I block this?

[Dolda2000]

Most distros come with mail relaying already denied by default. To relay mails, the connection must come from one of the authorized networks that are listed in /etc/mail/access.

[virgil66ro]

Thank's for your help.