/usr/share/munin/plugins/sendmail_mailtraffic is in munin-node 1.4.6-3ubuntu3.
This file is owned by root:root, with mode 0o755.
The actual contents of the file can be viewed below.
| 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 | #!/bin/sh
# -*- sh -*-
: << =cut
=head1 NAME
sendmail_mailtraffic - Plugin to monitor sendmail statistics
=head1 CONFIGURATION
This plugin uses the following configuration variables:
 [sendmail_mailstats]
  env.mailstats - Path to the "mailstats" command
=head2 DEFAULT CONFIGURATION
The default configuration for "mailstats" is to look for a binary called "mailstats" in PATH.
=head1 AUTHOR
Unknown author
=head1 LICENSE
Unknown license
=head1 MAGIC MARKERS
 #%# family=auto
 #%# capabilities=autoconf
=cut
if [ -n "$mailstats" ];
	then MAILSTATS=$mailstats;
	else MAILSTATS=`which mailstats 2>/dev/null`;
fi
if [ "$1" = "autoconf" ]; then
	if [ -n "$MAILSTATS" -a -x "$MAILSTATS" ]
		then echo yes
		else echo "no (no mailstats command)"
	fi
	exit 0
fi
if [ "$1" = "config" ]; then
	echo "graph_title Sendmail email volumes"
	echo "graph_order received sent"
	echo 'graph_vlabel bytes/${graph_period}'
	echo "graph_category sendmail"
	echo "received.label received"
	echo "sent.label sent"
	echo "received.max 1000000"
	echo "received.min 0"
	echo "sent.max 1000000"
	echo "sent.min 0"
	echo "received.type DERIVE"
	echo "sent.type DERIVE"
	exit 0
fi
$MAILSTATS -P | awk '/^ *T/ {
  received = received + $5
  sent = sent + $3
}
END {
  print "received.value", received
  print "sent.value", sent
}'
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