guru at unixarea.de
Wed Jan 5 15:59:29 UTC 2011
El dÃa Wednesday, January 05, 2011 a las 10:41:29AM -0500, Robert Fitzpatrick escribiÃ³:
> Keep getting calls from our provider at one location that our FreeBSD
> 8.0-RELEASE server is sending bursts of >1000 spam messages to >70K
> recipients. Since the first call a few weeks ago, I have MRTG and Mail
> Statistics graphs setup and see no spikes in traffic. Their last
> sighting was over the weekend and graphs show a reduction in traffic
> during that time as expected, again with no spikes in traffic or
> messages sent/received by our Postfix/Amavisd-maia MTA. All services on
> that server including SSH, SMTP and mail queue size all monitored by
> Nagios and have had no alerts from that server.
> Nonetheless, they claim I must have a bot and the mail is not passing
> through my own SMTP. And I suspect little traffic is needed for the
> alleged bursts. They have no envelope info. Can someone advise on what
> port(s) are available for bot detection and/or prevention? In all my
> years of running FreeBSD as mail gateways, this is the first time I've
> had this issue.
Check with tcpdump (on another host connected by a HUB, no switch, to
the box) if you can see that port 25 traffic of the NIC of the host;
that would be my 1st check to catch it...
If someone has lifted up your FreeBSD into a VM running on that bot, you
will not see this inside the FreeBSD, I think.
t +49-89-61308 351 - f +49-89-61308 399 - m +49-170-4527211
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