Denie's Tech Blog

#!/bin/bash

# Programmed by Denie Nataprawira (nataprawira@gmail.com)
# (c) 2011 — www.ayodiet.com
#
# Purposes:
# Deletes mailqueue files using matched keywords.
#

cd /var/spool/mqueue

if test -z $1
then
echo “The required parameter was empty. Please try again!”
echo “Format: delkeyw.sh [KEYWORDS]“
echo ” “
exit
fi

echo ” SEARCHING: \”$1\” from all files…”

find . -type f -exec grep -il ‘$1′ {} \; -exec rm -f {} \;

echo ” DONE: \”$1\” has been checked and deleted (if found).”

Source:
http://www.ducea.com/2008/08/19/sendmail-multiple-queues/

Sendmail will use by default a single mail queue. This is what most users will need, and if you don’t have any special requirement you will not care about this. Still for high traffic mail servers it might be useful to split the queue over several directories, as thousands of files in a single directory will become a performance penalty at some point and also processing the queue sequentially will become very slow.

This post will show how we can implement multiple mail queues with modern sendmail versions.
Let’s start by assuming we want to use 8 mail queues. First thing is to create the actual directories as sendmail will not do this by default:

mkdir /var/spool/mqueue/q{1,2,3,4,5,6,7,8}

And fix the permissions to the ones of the original folder /var/spool/mqueue. For ex. this might look like:

chown -R root:smmsp /var/spool/mqueue/q*

using a default sendmail install running on debian. Fix the users to the specific ones found on your system (ls -al /var/spool/mqueue if you are uncertain of this).

Next, we need to enable the multiple queues in the sendmail configuration. For this we will edit sendmail.mc (normally found under /etc/mail) and append one line:

define(`QUEUE_DIR', `/var/spool/mqueue/q*')dnl

and now regenerate sendmail.cf; this is done normally running:

m4 sendmail.mc > /etc/mail/sendmail.cf

(fix your paths appropriately), or if you are using debian sendmail you can just run make all in /etc/mail.

After restarting sendmail, it will start using the multiple queues we defined. Running mailq will output each of the queues:

#mailq
/var/spool/mqueue/q6 is empty
/var/spool/mqueue/q4 is empty
/var/spool/mqueue/q3 is empty
/var/spool/mqueue/q2 is empty
/var/spool/mqueue/q5 is empty
/var/spool/mqueue/q1 is empty
/var/spool/mqueue/q7 is empty
/var/spool/mqueue/q8 is empty
Total requests: 0

Note: if you want to add more folders to the configuration all you have to do is to create the respective folders, set the appropriate permissions and restart sendmail.

If you had existing mails in the queue (most likely if you were looking for this solution), if you want them still processed, move them from /var/spool/mqueue in one of the newly created queues (q1 for ex).

Individual queue directories can be symbolic links to other partitions to spreads load among multiple disks. Queue IDs are unique across queues so you can move the items among queues if you have to.

This is what I’m currently using on “sendmail.mc”. So far quite good and I can blast around 100K emails within few hours. Enjoy! Read more …

# Copyright (c) 2001 Sendmail, Inc. and its suppliers.
# All rights reserved.
#
# By using this file, you agree to the terms and conditions set
# forth in the LICENSE file which can be found at the top level of
# the sendmail distribution.
#
# $Id: TUNING,v 1.16 2001/08/19 21:03:38 gshapiro Exp $
# Read more …

This is a quick walk through on how to set up domain keys on Centos 5 using sendmail. It should also be very similar for Redhat or Fedora.