ln -s /usr/share/munin/plugins/postfix_mailqueue /etc/munin/plugins/postfix_mailqueue
ln -s /usr/share/munin/plugins/postfix_mailstats /etc/munin/plugin
s/postfix_mailstats
ln -s /usr/share/munin/plugins/postfix_mailvolume /etc/munin/plugins/postfix_mailvolume
service munin-node restart
5分後を待つ
