Floods of Emails Coming In To /var/spool/mqueue

[Robert L Cochran]

I have a server box running Fedora Core 2 which hasn't been updated 
since sendmail 8.12.11-4.6. It has two mailman lists running on it which 
are important to me. Also, over the last few years, I've set up 2-4 
email accounts which are hosted by the server for the convenience of 
guests who have stayed with us for vacations and so on. I haven't paid 
much attention to either mailman or the email accounts over the years -- 
they didn't cause an overt problem until now. Today I finally started 
investigating why some of my posts to the mailing list were not coming 
back to me as expected, and discovered that my /var/spool/mqueue 
directory is monstrously bloated. Look at the '20668416' in the 
directory listing (although I'm not sure what that number means, except 
to indicate the directory has a lot of files in it):

drwx------   2 root   mail   20668416 Jan  6 15:58 mqueue

I deleted the folder and then recreated it with the same permissions. 
But I'm still getting floods of emails from somewhere. 279 in the past 
hour or so. They look like spam.

How can I put a stop to these emails -- do I need procmail recipes? Can 
I configure sendmail to drop anything not coming in for a valid user? Or 
is it best to upgrade to the latest version of Fedora and work on 
tightening up processing of incoming emails? Is there any way of 
stopping the tidal wave of spam? What is a sensible approach to fixing 
this?

Thanks

Bob Cochran
Greenbelt, Maryland, USA