Originally Posted by RTM

mmdf is the SCO mail daemon - the files being created are probably email to be sent. If it's like Sendmail, the mail will still be running even though you killed the mmdf process. This means killing the process doesn't stop email from being created and put into the queue to be sent - it just means you can't receive mail on that server (again, assuming MMD works like Sendmail).

Check what type of files are being put into the directories - file * should list them. If they are type ascii, cat a couple of them. You will probably find they are emails. Check to see if any of the files seem to be spam. You may not have your mmdf set up properly and could be a relay for a spammer.

Killing off the mmdf probably didn't do a thing for you. And if the system is slow (and email isn't going out), then you probably have a problem with DNS (again, this is assuming that mmdf works like Sendmail) OR with someone using your system as a mail relay.

mmdf relay
MMDF overview

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