proxy monitor

proxy_monitor.sh

#!/bin/sh
# $Id$ */
#
#       proxy_monitor.sh
#       Copyright (C) 2006 Scott Ullrich
#       All rights reserved.
#
#       Redistribution and use in source and binary forms, with or without
#       modification, are permitted provided that the following conditions are met:
#
#       1. Redistributions of source code must retain the above copyright notice,
#          this list of conditions and the following disclaimer.
#
#       2. Redistributions in binary form must reproduce the above copyright
#          notice, this list of conditions and the following disclaimer in the
#          documentation and/or other materials provided with the distribution.
#
#       THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
#       INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
#       AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
#       AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
#       OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
#       SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
#       INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
#       CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
#       ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
#       POSSIBILITY OF SUCH DAMAGE.
#

set -e

LOOP_SLEEP=55

if [ -f /var/run/squid_alarm ]; then
        rm /var/run/squid_alarm
fi

# Sleep 5 seconds on startup not to mangle with existing boot scripts.
sleep 5

# Squid monitor 1.2
PMPROCESS=`ps aux | grep -v grep | grep -c 'proxy_monitor.sh'`
print "$PMPROCESS" | logger daemon.info -i -t Squid_Alarm
sleep 3
if [ ${PMPROCESS} -lt 3 ]; then
        echo 'Proxy monitor working...' | logger -p daemon.info -i -t Squid_Alarm
        while [ /bin/true ]; do
                if [  ! -f /var/run/squid_alarm ]; then
                        NUM_PROCS=`ps auxw | grep "[s]quid -D"|awk '{print $2}'| wc -l | awk '{ print $1 }'`
                        if [ $NUM_PROCS -lt 1 ]; then
                                    # squid is down
                                    echo "Squid has exited.  Reconfiguring filter." | \
                                                logger -p daemon.info -i -t Squid_Alarm
                                    echo "Attempting restart..." | logger -p daemon.info -i -t Squid_Alarm
                                    /usr/local/etc/rc.d/squid.sh start
                                    sleep 3
                                    echo "Reconfiguring filter..." | logger -p daemon.info -i -t Squid_Alarm
                                    /etc/rc.filter_configure_sync
                                    touch /var/run/squid_alarm
                        fi
            fi
            NUM_PROCS=`ps auxw | grep "[s]quid -D"|awk '{print $2}'| wc -l | awk '{ print $1 }'`
            if [ $NUM_PROCS -gt 0 ]; then
                        if [ -f /var/run/squid_alarm ]; then
                                    echo "Squid has resumed. Reconfiguring filter." | \
                                                logger -p daemon.info -i -t Squid_Alarm
                                                /etc/rc.filter_configure_sync
                                    rm /var/run/squid_alarm
                        fi
            fi
            sleep $LOOP_SLEEP
        done
fi

if [ -f /var/run/squid_alarm ]; then
        rm /var/run/squid_alarm
fi