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Sendmail - SMTP Issues

Sendmail - SMTP Issues

Sendmail - SMTP Issues


I'm having issues with a Sendmail box here running SMTP.

I'm noticing that the service fails every 10-15 minutes.

After a lot of troubleshooting, I noticed that the SMTP listening daemons seem to be the problem.

It looks as though the spam coming in to the box is taking up all of the listening daemons. When the system goes down, I tried a net stat and noticed none of the smtp listening daemons are running. I killed a few processes from the spam and the daemons became free so the system was up and running.

The system is not even receiving a lot of spam but this is becoming very annoying.

Anyone have any ideas? This system has been running fine for a year and the spam has been pretty much the same every since then and never failed to operate. The issue started after a reboot of the system

So in brief, this issue started after a reboot of the system.

When the SMTP goes down, it stays down for 5 minutes and then comes back up.
When it goes down, I list the processes and I notice that SMTP listening on port 25 is not running.

I notice about 20-30 smtp connections on port 25 (mostly spam). Does anyone think theres a problem with email flow? Why would so many connections hog the smtp port 25 processes and for such a long duration?

Any ideas? thanks

Thanks all

Im running Suse 8.1

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