email question - user overloaded the server

[pfulhosting]

The user: "[email protected]" was sending the email below to a mailbox user on the same domain: [email protected] by the ten's of thousands per hour resulting in a 300+ load on the server. Each mailbox also had an auto-responder enabled. The only way to get the server back up was to reboot and remove both email boxes and responders - the load dropped to .2. The account owner swears (of course) that they were not doing anything unusual or running any weird scripts. Any ideas about how this happened and how to prevent similar issues in the future?

>From [email protected] Tue Aug 22 04:05:43 2006
Received: from ssautoch by cp1.powerfulhosting.com with local (Exim 4.52)
id 1GFU4k-00076n-Kl
for [email protected]; Tue, 22 Aug 2006 04:05:43 -0700
X-Boxtrapper: 2q_HxXErpRWTa3pvD0Rhcbgp2oft9w2j
From: [email protected]
To: [email protected]
Subject: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: Re: 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(FORUM READERS - SPACE RESTRICTS ME FROM ENTERING ALL THE "Re:'s" - THERE WERE THOUSANDS OF THEM IN THE SUBJECT LINE. THE SUBJECT LINE IN THE AUTO RESPONDER WAS SET AS: Re: %subject%)
Your email requires verification verify#UO1IeTovWY_u73byqrVHzRv_hnv0fsqe
Message-Id: <[email protected]>
Date: Tue, 22 Aug 2006 04:05:42 -0700

 

[ramprage]

http://www.webhostgear.com/3.html

The maximum each domain can send out per hour (0 is unlimited): If you have clients on your server I suggest entering a high value such as 500. This limits the sending amount of mail for the entire domain, not per email address. If they start reporting they can't send messages out you can increase it.

The number of times users are allowed to check their mail using pop3 per hour: 60 is recommended. That's 1 check per minute which is high enough.

 

[chirpy]

I've seen this happen many times. Usually it's ping-pong between two accounts with boxtrapper or autoresponders enabled - a very good example as to why you should not use either.