start-munin.sh

#!/bin/bash


NODES=${NODES:-}
TZ=${TZ:UTC}
SNMP_NODES=${SNMP_NODES:-}
SSH_NODES=${SSH_NODES:-}
MUNIN_USERS=${MUNIN_USERS:-${MUNIN_USER:-user}}
MUNIN_PASSWORDS=${MUNIN_PASSWORDS:-${MUNIN_PASSWORD:-password}}
MAIL_CONF_PATH='/var/lib/munin/.mailrc'
SMTP_USE_TLS=${SMTP_USE_TLS:-false}
SMTP_ALWAYS_SEND=${SMTP_ALWAYS_SEND:-true}
SMTP_MESSAGE_DEFAULT='[${var:group};${var:host}] -> ${var:graph_title} -> warnings: ${loop<,>:wfields  ${var:label}=${var:value}} / criticals: ${loop<,>:cfields  ${var:label}=${var:value}}'
SMTP_MESSAGE="${SMTP_MESSAGE:-$SMTP_MESSAGE_DEFAULT}"
GRAPH_DATA_SIZE=${GRAPH_DATA_SIZE:-}

# set timezone
if [[ -e /usr/share/zoneinfo/${TZ} ]]; then
  rm -f /etc/localtime
  ln -s /usr/share/zoneinfo/${TZ} /etc/localtime
  echo ${TZ} > /etc/timezone
fi

truncate -s 0 "${MAIL_CONF_PATH}"

# set volume ownerships
chown -R munin:munin /var/log/munin
chown -R munin:munin /var/lib/munin
chown -R munin:munin /var/run/munin
chown -R munin:munin /var/cache/munin

if [ "${SMTP_USE_TLS}" = true ] ; then
  cat >> "${MAIL_CONF_PATH}" <<EOF
set smtp-use-starttls
set ssl-verify=ignore
EOF
fi

if [ -n "${SMTP_HOST}" -a -n "${SMTP_PORT}" ] ; then
  cat >> "${MAIL_CONF_PATH}" <<EOF
set smtp=smtp://${SMTP_HOST}:${SMTP_PORT}
EOF
fi

if [ -n "${SMTP_USERNAME}" -a -n "${SMTP_PASSWORD}" ] ; then
  cat >> "${MAIL_CONF_PATH}" <<EOF
set smtp-auth=login
set smtp-auth-user=${SMTP_USERNAME}
set smtp-auth-password=${SMTP_PASSWORD}
EOF
fi

grep -q 'contact.mail' /etc/munin/munin.conf; rc=$?
if  [ $rc -ne 0 -a -n "${ALERT_RECIPIENT}" -a -n "${ALERT_SENDER}" ] ; then
  echo "Setup alert email from ${ALERT_SENDER} to ${ALERT_RECIPIENT}"
  echo "contact.mail.command mail -r ${ALERT_SENDER} -s '${SMTP_MESSAGE}' ${ALERT_RECIPIENT}" >> /etc/munin/munin.conf
  if [ "${SMTP_ALWAYS_SEND}" = true ] ; then
    echo 'contact.mail.always_send warning critical' >> /etc/munin/munin.conf
  fi
fi

# generate the Munin auth username/password file
if [ ! -f /etc/munin/htpasswd.users ]; then
  uc=0
  IFS=' ' read -ra ARR_USERS <<< "$MUNIN_USERS"
  IFS=' ' read -ra ARR_PASSWORDS <<< "$MUNIN_PASSWORDS"
  for u in "${ARR_USERS[@]}"; do
    printf "${u}:`openssl passwd -apr1 ${ARR_PASSWORDS[uc]}`\n" >> /etc/munin/htpasswd.users
    (( uc++ ))
  done
fi

if [ -z "$GRAPH_DATA_SIZE" ]
then
  sed -i 's/^.*graph_data_size.*$/#graph_data_size custom 2d, 10m for 14d, 15h for 90d, 30m for 1y, 12h for 10y/g' /etc/munin/munin.conf
else
  sed -i "s/^.*graph_data_size.*$/graph_data_size ${GRAPH_DATA_SIZE}/g" /etc/munin/munin.conf
fi

# clean old node list
sed -i '/^#--start-nodes--#/,/^#--end-nodes--#$/{/^#--start-nodes--#/!{/\$/!d}}' /etc/munin/munin.conf

# generate node list
for NODE in $NODES
do
  NAME=`echo $NODE | cut -d ":" -f1`
  HOST=`echo $NODE | cut -d ":" -f2`
  PORT=`echo $NODE | cut -d ":" -f3`
  if [ ${#PORT} -eq 0 ]; then
      PORT=4949
  fi
  if ! grep -q "'^$HOST$'" /etc/munin/munin.conf ; then
    cat << EOF >> /etc/munin/munin.conf
[$NAME]
    address $HOST
    use_node_name yes
    port $PORT

EOF
    echo "Added node '$NAME' '$HOST'"
    fi
done

# generate snmp node list
for NODE in $SNMP_NODES
do
  NAME=`echo $NODE | cut -d ":" -f1`
  HOST=`echo $NODE | cut -d ":" -f2`
  PORT=`echo $NODE | cut -d ":" -f3`
  if [ ${#PORT} -eq 0 ]; then
      PORT=4949
  fi
  if ! grep -q "'^$HOST$'" /etc/munin/munin.conf ; then
    cat << EOF >> /etc/munin/munin.conf
[$NAME]
    address $HOST
    use_node_name no
    port $PORT

EOF
    echo "Added SNMP node '$NAME' '$HOST'"
    fi
done

for SSH_NODE in $SSH_NODES
do
  NAME=`echo $SSH_NODE | cut -d ":" -f1`
  HOST=`echo $SSH_NODE | cut -d ":" -f2`
  PORT=`echo $SSH_NODE | cut -d ":" -f3`
  if [ ${#PORT} -eq 0 ]; then
      PORT=4949
  fi
  if ! grep -q "'^$HOST$'" /etc/munin/munin.conf ; then
    cat << EOF >> /etc/munin/munin.conf
[$NAME]
    address ssh://$HOST/usr/bin/nc localhost 4949
    use_node_name yes
    port $PORT

EOF
    echo "Added SSH node '$NAME' '$HOST'"
    fi
done

# append end node list tag
echo "#--end-nodes--#" >> /etc/munin/munin.conf


[ -d /var/cache/munin/www ] || mkdir /var/cache/munin/www
# placeholder html to prevent permission error
if [ ! -e /var/cache/munin/www/index.html ]; then
cat << EOF > /var/cache/munin/www/index.html
<html>
<head>
  <title>Munin</title>
</head>
<body>
Munin has not run yet.  Please try again in a few moments.
</body>
</html>
EOF
chown munin:munin -R /var/cache/munin/www
chmod g+w /var/cache/munin/www/index.html
fi

# remove err'ing xconsole rsyslog config
mv /etc/rsyslog.d/50-default.conf /etc/rsyslog.d/50-default.conf.tmp
head -n -4 /etc/rsyslog.d/50-default.conf.tmp > /etc/rsyslog.d/50-default.conf
rm /etc/rsyslog.d/50-default.conf.tmp

chgrp munin /var/log/munin /var/run/munin /var/lib/munin
chmod g+rw /var/log/munin /var/run/munin /var/lib/munin
# Clear crashed run
rm -f /var/run/munin/*

# start rsyslogd
/usr/sbin/rsyslogd
# start cron
/usr/sbin/cron
# Issue: 'NUMBER OF HARD LINKS > 1' prevents cron exec in container
# https://github.com/phusion/baseimage-docker/issues/198
touch /etc/crontab /etc/cron.d/*
# start local munin-node
#/usr/sbin/munin-node
echo "Using the following munin nodes:"
echo $NODES
echo "(ssh) $SSH_NODES"
echo "(snmp) $SNMP_NODES"
# start spawn-cgi to enable CGI interface with munin (dynamix graph generation)
spawn-fcgi -s /var/run/munin/fcgi-graph.sock -U munin -u munin -g munin /usr/lib/munin/cgi/munin-cgi-graph
# start nginx
/usr/sbin/nginx
# show logs
echo "Tailing syslog and munin-update log..."
tail -F /var/log/syslog /var/log/munin/munin-update.log & pid=$!
echo "tail -F running in $pid"

sleep 1

trap "echo 'stopping processes' ; kill $pid $(cat /var/run/munin/munin-node.pid) $(cat /var/run/nginx.pid) $(cat /var/run/crond.pid) $(cat /var/run/rsyslogd.pid)" SIGTERM SIGINT

echo "Waiting for signal SIGINT/SIGTERM"
wait