campbell at cnpapers.com
Thu Apr 21 19:48:07 IST 2005
[ The following text is in the "iso-8859-1" character set. ]
[ Your display is set for the "US-ASCII" character set. ]
[ Some characters may be displayed incorrectly. ]
If you're concerned about an idle gateway, and these are your DNS MX boxes,
I think (?) you can set up your MX records to be equal priority with a short
TTL, thus creating a round-robin DNS.
Of course, this won't help if this attack is rapid and short lived, but it
may delegate some of the mail to the secondary alleviating some of the
I could be wrong here. Please let the list correct me if so.
campbell at cnpapers.com
----- Original Message -----
From: "AP" <pearsoa at SUNBEAM.COM>
To: <MAILSCANNER at JISCMAIL.AC.UK>
Sent: Thursday, April 21, 2005 10:52 AM
Subject: Stop inbound
> Hey Guys,
> Is there a way that I can shutdown the reception of mail to the inbound
> queue while still allowing MailScanner to process what's currently in the
> inbound queue and still allow the delivery of mail in the post-processing
> I know that I could turn off port 25 on the Firewall to the specific mail
> gateway but I would like to do this on the Mail Gateway itself.
> Here's my reason. We sometimes early in the mornings (3-4am) get directed
> SPAM attacks that loads up our primary mail gateway. Our inbound queues
> can get quite large and the primary mail gateway will continue receiving
> the mail without regard to how large the inbound queue is getting. We can
> sometimes get 3000-5000 messages in the inbound queue while our secondary
> mail gateway is practically idle.
> I was thinking that I could write a mailqin monitoring script that would
> poll the queue every 5 minutes and if it has reached some kind of
> threshold, say 500-1000 messages, it would then stop the receiving of
> inbound mail until MailScanner had processed the queue down to some
> minimum, say 100 messages, before it would start back the receiving of
> mail. That way the secondary mail gateway would start taking on some of
> the load and we could avoid some of the message delays that we get because
> of the backlog.
> Our primary and secondary mail gateways are fairly heavy duty boxes,
> class with dual hyper-threaded processors and lots of memory so it is not
> that the boxes are underpowered it's just that the secondary box is being
> under utilized.
> Any thoughts or suggestions would be welcome. If there is a better way to
> handle this I would be interested to know.
> ------------------------ MailScanner list ------------------------
> To unsubscribe, email jiscmail at jiscmail.ac.uk with the words:
> 'leave mailscanner' in the body of the email.
> Before posting, read the Wiki (http://wiki.mailscanner.info/) and
> the archives (http://www.jiscmail.ac.uk/lists/mailscanner.html).
> Support MailScanner development - buy the book off the website!
------------------------ MailScanner list ------------------------
To unsubscribe, email jiscmail at jiscmail.ac.uk with the words:
'leave mailscanner' in the body of the email.
Before posting, read the Wiki (http://wiki.mailscanner.info/) and
the archives (http://www.jiscmail.ac.uk/lists/mailscanner.html).
Support MailScanner development - buy the book off the website!
More information about the MailScanner