Resend Postfix messages stuck in mail queue to another address

Update 2015-02-19: Based on suggestions from David Keegel, I’ve tweaked the script to properly hold/unhold messages, and include the sender’s email address in the message envelope.

Ever had somebody give you a bad email address, and the messages pile up in your Postfix mail queue? Even if you have the right address to send the stuck emails to, Postfix (at least on CentOS 5.x based on all my research) provides no easy way to:

Resend all those messages to the new address
Remove the old stuck messages

We needed this functionality badly for our business, where we unfortunately get bad email addresses given to us all the time. So, using my marginal bash skills and several hours of my time, I whipped up the script below to automate this process.

Caveat: I’ve tested this script extensively with Postfix on CentOS 5.x, but nowhere else, really. So test first, use at your own risk!

#!/bin/bash # This script allows sending of messages stuck in the Postfix queue to another # email address. Useful if the original email address is bad. if [ $# -ne 2 ]; then echo "Usage: reroute-queued-email-messages.sh <oldaddress> <newaddress>" exit 1 fi OLD_ADDRESS="$1" NEW_ADDRESS="$2" MAILQ=`which mailq` POSTCAT=`which postcat` POSTSUPER=`which postsuper` SENDMAIL=`which sendmail` TAIL=`which tail` GREP=`which grep` AWK=`which awk` SED=`which sed` # Pulls queue IDs for all messages sent to the original address. function get_ids_by_address { $MAILQ | $TAIL -n +2 | $GREP -v '^ *(' | $AWK -v address="$1" 'BEGIN { RS = "" } { if ($8 == address) print $1 }' } MESSAGE_IDS=`get_ids_by_address $OLD_ADDRESS` # Loop through each message ID, output the message, and pipe it through # sendmail to the new address. for message_id in $MESSAGE_IDS; do # Puts the message on hold. $POSTSUPER -h $message_id # Extract the sender. sender=`$POSTCAT -q $message_id | $GREP -m 1 '^From: ' | $SED '/^From: */!d; s///; q'` # sed gets rid of the leading queue metadata, grep -v gets rid of the # metadata markers. $POSTCAT -q $message_id | $SED -n '/MESSAGE CONTENTS/,$p' | $GREP -v "^\*\*\*.*\*\*\*$" | sendmail -f "$sender" $NEW_ADDRESS echo "Delivered message ID $message_id to $NEW_ADDRESS" done echo -n "Remove old messages from mail queue? [y/N]: " read delete if [ "$delete" = "y" ]; then for message_id in $MESSAGE_IDS; do # Deletes the message from the mail queue by queue ID. $POSTSUPER -d $message_id echo "Deleted message ID $message_id from queue" done else for message_id in $MESSAGE_IDS; do # Takes the message off hold. $POSTSUPER -H $message_id done echo "The following messages were left in the mail queue:" echo "$MESSAGE_IDS" fi exit 0