Add doc and helper scripts

README.md

@@ -0,0 +1,25 @@
+Low volume postfix_mailqueue munin plugin
+=========================================
+
+The original postfix_mailqueue plugin delivered with munin does very well
+in many aspects. But it has a design related problem: to measure the number
+of mails per queue (active, incomming, deferred, ...) it counts the entries
+in the corresponding spool directories every 5 minutes (when munin core asks).
+If a mail only stays a short time in a queue (especially active and incomming
+queues) it won't get recognized by postfix_mailqueue.
+
+Since on my low volume mailserver I'm interested in the total number of sent/
+recieved messages in the last 5 minutes (for the deferred and hold queues the
+original method is good enough since a mail there probably stays longer than
+5 minutes) I changed the behavior and meaning of the "active" and "incomming"
+graphs to "outgoing" (to the network) and "incomming" (from the network).
+To determine the number of mails for these graphs the recent (5 minutes, hardcoded)
+syslog entries are grep'ed for signaling sequences indicating some kind of
+action of postfix.
+
+syslog5mins
+-----------
+
+This little script returns the entries of a (syslog created) file of the last
+5 minutes.
+**You should modify the scripts location in postfix_mailqueue script!**

postfix_mailqueue

@@ -78,6 +78,9 @@ munin-node.
 
 =cut
 
+MAILLOG="/var/log/mail.log"
+SYSLOG5MINS="/opt/syslog5mins"
+
 # atempt to get spooldir via postconf, but environment overrides.
 
 # Remember that postconf is not available unless postfix is.
@@ -127,10 +130,10 @@ cd $SPOOLDIR >/dev/null 2>/dev/null || {
 }
 
 cat <<EOF
-outgoing.value `/opt/syslog5mins /var/log/mail.log | grep "postfix/smtp\[.*status=sent" | wc -l`
+outgoing.value `$SYSLOG5MINS $MAILLOG | grep "postfix/smtp\[.*status=sent" | wc -l`
 deferred.value `(test -d deferred && find deferred -type f ) | wc -l`
 maildrop.value `(test -d maildrop && find maildrop -type f ) | wc -l`
-incoming.value `/opt/syslog5mins /var/log/mail.log | grep "postfix/pipe\[.*status=sent" | wc -l`
+incoming.value `$SYSLOG5MINS $MAILLOG | grep "postfix/pipe\[.*status=sent" | wc -l`
 corrupt.value `(test -d corrupt && find corrupt -type f ) | wc -l`
 hold.value `( test -d hold && find hold -type f ) | wc -l`
 EOF

syslog5mins

@@ -0,0 +1,15 @@
+#!/bin/bash
+
+if [ "$1" == "" ]; then
+	echo "No file given!"
+	exit 1
+fi
+
+for (( i = 4; i >= 0; i-- )) ; do
+	# In %_d the underscore is important since it demands `date`
+	# to pad with spaces (like syslog for e.g. "Jan  1" to "Jan  9")
+	# instead of zeros.
+	dstring=`LANG=C date -d "-$i min" +"%b %_d %R"`
+	#echo "Entries for '$dstring':"
+	grep "^$dstring:.. " $1
+done