file: checkqueuesize.sh
 
#!/bin/sh
 
#########################################################
#                                                       #
# Script to check the number of messages in a qmail     #
# queue and sends an email alert when it is over the    #
# given amount.                                         #
#                                                       #
# Author: Neil Bittner                                  #
# Version: 0.1                                          #
#                                                       #
#########################################################
 
EMAIL=youremail@domain.com
 
 
validNumber() {
  case "$1" in
     *[!0-9]*)   return 1;;  # string contains invalid chars.
     *)          return 0;;  # only digits from 0-9
  esac
}
 
if [ $# -eq 1 ]; then
  if validNumber "$1" ; then
    msgCap=$1
    largeQueueMessage="The mail queue on `hostname -f` has over $msgCap messages.  You should try cleaning the bounce messages out of the queue."
    messageSub="`hostname -f` has over $msgCap messages in the queue"
    messageTo="$EMAIL"
    messageFrom="root@`hostname -f`"
 
    if [ -f /var/qmail/bin/qmail-qstat ]; then
      MESSAGES="`/var/qmail/bin/qmail-qstat | head -n 1 | awk '{ print substr($0,20,length($0))}'`"
      if [ $MESSAGES -gt $msgCap ]; then
        echo "The queue needs to be cleaned!"
        echo "$largeQueueMessage" | mail -s "$messageSub" "$messageTo" -- -f "$messageFrom"
      fi
    fi
  else
    echo "Invalid number \"$1\""
    echo "Usage:"
    echo "   $0 MESSAGES_REQUIRED"
  fi
else
  echo "Usage:"
  echo "   $0 MESSAGES_REQUIRED"
fi