Matejunkie

#!/bin/sh
 
#   This program is free software; you can redistribute it and/or modify
#   it under the terms of the GNU General Public License as published by
#   the Free Software Foundation; either version 2 of the License, or
#   (at your option) any later version.
#
#   This program is distributed in the hope that it will be useful,
#   but WITHOUT ANY WARRANTY; without even the implied warranty of
#   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#   GNU General Public License for more details.
#
#   You should have received a copy of the GNU General Public License
#   along with this program; if not, write to the Free Software
#   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 
PROGNAME=`basename $0`
VERSION="Version 1.1,"
AUTHOR="2009, Mike Adolphs (http://www.matejunkie.com/)"
 
print_version() {
    echo "$VERSION $AUTHOR"
}
 
print_help() {
    print_version $PROGNAME $VERSION
    echo ""
    echo "Description"
    echo "$PROGNAME is a Nagios plugin to check the Apache's server status"
    echo "via the famous mod_status. Make sure, that you have permissions"
    echo "to access http://yourserver:port/server-status and that the Nagios"
    echo "User has the right to call 'ps ax' and 'ps -Ao pcpu,args', otherwise"
    echo "the script refuses to work. This will likely occur only on hardened"
    echo "systems."
    echo ""
    echo "How it works:"
    echo "The script first checks whether Apache is running and then gets the"
    echo "server's status page. Req/sec are generated by a diff from the amount"
    echo "of total requests being served by the Apache due to the fact that"
    echo "mod_status only provides an average value for the server's runtime."
    echo "The same applies to the CPU utilization value. Therefore we use ps"
    echo "to get more realistic data."
    echo ""
    echo "The script itself is written sh-compliant and free software under"
    echo "the terms of the GPLv2. There's a default value for each variable. It"
    echo "probably works just out of the box?"
    echo ""
    echo "$PROGNAME -H/--hostname localhost -p/--port 80 -t/--timeout 3 -o \$HOME"
    echo "-b /usr/sbin -e"
    echo ""
    echo "Options:"
    echo "  -b/--binary-dir)"
    echo "     You might need to choose the directory where your apache2 binary is"
    echo "     located. Otherwise the check will fail. Default is: /usr/sbin"
    echo "  -H/--hostname)"
    echo "     You may define a hostname. Default is: localhost"
    echo "  -p/--port)"
    echo "     You may define a port. Default is: 80"
    echo "  -t/--timeout)"
    echo "     You might want to define a timeout (in sec) for the wget call. Default"
    echo "     is: 3"
    echo "  -o/--output-directory)"
    echo "     You may define a directory where a local copy of server-status"
    echo "     is being stored to spare the Apache. Default is: $HOME"
    echo "  -e/--extended-info)"
    echo "     Provides additional performance data: Total amount of requests, total"
    echo "     amount of transferred bytes, bytes per second, bytes per request and"
    echo "     The servers uptime. Default is off."
    echo "  -wr/--warning-req)"
    echo "     Sets a warning level for requests per second and must be used together"
    echo "     with the -c/--critical-req option. Default is off."
    echo "  -cr/--critical-req)"
    echo "     Sets a critical level for requests per second and must be used together"
    echo "     with the -w/--warning-req option. Default is off."
    exit $ST_UK
}
 
ST_OK=0
ST_WR=1
ST_CR=2
ST_UK=3
 
hostname="localhost"
port=80
timeout=3
output_dir=$HOME
binary_dir="/usr/sbin"
ext_info=0
running=0
 
wcdiff_req=0
wclvls_req=0
 
while test -n "$1"; do
    case "$1" in
        --help|-h)
            print_help
            exit $ST_UK
            ;;
        --version|-v)
            print_version $PROGNAME $VERSION
            exit $ST_UK
            ;;
        --hostname|-H)
             hostname=$2
             shift
             ;;
        --port|-p)
             port=$2
             shift
             ;;
        --timeout|-t)
             timeout=$2
             shift
             ;;
        --output_directory|-o)
             output_dir=$2
             shift
             ;;
        --binary_dir|-b)
             binay_dir=$2
             shift
             ;;
        --extendd-info|-e)
             ext_info=1
             ;;
        --warning-req|-wr)
             warn_req=$2
            shift
            ;;
        --critical-req|-cr)
             crit_req=$2
            shift
            ;;
        *)
            echo "Unknown argument: $1"
            print_help
            exit $ST_UK
            ;;
    esac
    shift
done
 
# get functions
get_wcdiff_req() {
    if [ ! -z "$warn_req" -a ! -z "$crit_req" ]
    then
        wclvls_req=1
 
        if [ ${warn_req} -gt ${crit_req} ]
        then
            wcdiff_req=1
        fi
    elif [ ! -z "$warn_req" -a -z "$crit_req" ]
    then
        wcdiff_req=2
    elif [ -z "$warn_req" -a ! -z "$crit_req" ]
    then
        wcdiff_req=3
    fi
}
 
get_processes() {
    ps ax | grep -c ${binary_dir}/[a]pache2
}
 
get_status() {
    wget -q -t 3 -T ${timeout} http://${hostname}:${port}/server-status?auto -O ${output_dir}/server-status
    sleep 1
    wget -q -t 3 -T ${timeout} http://${hostname}:${port}/server-status?auto -O ${output_dir}/server-status.1
}
 
get_total_req() {
    total_req=`cat ${output_dir}/server-status | grep 'Total Accesses:' | awk '{print $3}'`
}
 
get_total_kb() {
    total_kb=`cat ${output_dir}/server-status | grep 'Total kBytes:' | awk '{print $3}'`
}
 
get_uptime() {
    uptime=`cat ${output_dir}/server-status | grep 'Uptime:' | awk '{print $2}'`
}
 
get_cpu_load() {
    cpu_load="$(cpu_load=0; ps -Ao pcpu,args | grep '/usr/sbin/apache2' | awk '{print $1}' | while read line
    do
        cpu_load=`echo "scale=3; $cpu_load + $line" | bc -l`
    echo $cpu_load
    done)"
    cpu_load=`echo $cpu_load | awk '{print $NF}' | sed 's/^\./0./'`
}
 
get_req_psec() {
    tmp1_req_psec=`cat ${output_dir}/server-status | grep 'Total Accesses:' | awk '{print $3}'`
    tmp2_req_psec=`cat ${output_dir}/server-status.1 | grep 'Total Accesses:' | awk '{print $3}'`
    req_psec=`echo "scale=2; ${tmp2_req_psec} - ${tmp1_req_psec}" | bc -l`
}
 
get_bytes_psec() {
    bytes_psec=`cat ${output_dir}/server-status | grep 'BytesPerSec:' | awk '{print $2}' | sed 's/^\./0./'`
}
 
get_bytes_preq() {
    bytes_preq=`cat ${output_dir}/server-status | grep 'BytesPerReq:' | awk '{print $2}' | sed 's/^\./0./'`
}
 
get_wkrs_busy() {
    wkrs_busy=`cat ${output_dir}/server-status | grep 'BusyWorkers:' | awk '{print $2}'`
}
 
get_wkrs_idle() {
    wkrs_idle=`cat ${output_dir}/server-status | grep 'IdleWorkers:' | awk '{print $2}'`
}
 
# check functions
check_processes() {
    if [ $1 -lt 1 ]
    then
        echo "UNKNOWN - Your Apache server seems not to run. Is your Nagios privileged to run 'ps ax' and is the Apache2 binary really loc
ated in $binary_dir?"
        exit $ST_UK
    fi
}
 
check_output() {
    stat_output=`stat -c %s ${output_dir}/server-status`
    if [ "$stat_output" = 0 ]
    then
        echo "UNKNOWN - Local copy of server-status is empty. Are we allowed to access http://${hostname}:${port}/server-status?"
        exit $ST_UK
    fi
}
 
# Let's do this
get_wcdiff_req
 
if [ "$wcdiff_req" = 1 ]
then
    echo "Please adjust your warning/critical thresholds. The warning must be lower than the critical level!"
    exit $ST_UK
elif [ "$wcdiff_req" = 2 ]
then
    echo "Please also set a critical value when you want to use warning/critical thresholds!"
    exit $ST_UK
elif [ "$wcdiff_req" = 3 ]
then
    echo "Please also set a warning value when you want to use warning/critical thresholds!"
    exit $ST_UK
else
    running=`get_processes`
    check_processes $running
 
    get_status
    check_output
 
    case $ext_info in
        1)
            get_req_psec; get_cpu_load; get_uptime; get_wkrs_busy; get_wkrs_idle;
            get_total_req; get_total_kb; get_bytes_psec; get_bytes_preq;
            perfdata="'req_psec'=$req_psec 'cpu_load'=$cpu_load 'uptime'=$uptime 'workers_busy'=$wkrs_busy 'workers_idle'=$wkrs_idle 'tota
l_req'=$total_req 'total_kb'=$total_kb 'bytes_psec'=$bytes_psec 'bytes_preq'=$bytes_preq"
            ;;
        *)
            get_req_psec; get_cpu_load; get_wkrs_busy; get_wkrs_idle;
            perfdata="'req_psec'=$req_psec 'cpu_load'=$cpu_load 'workers_busy'=$wkrs_busy 'workers_idle'=$wkrs_idle"
            ;;
    esac
 
    if [ ${wclvls_req} = 1 ]
    then
        if [ ${req_psec} -ge ${warn_req} -a ${req_psec} -lt ${crit_req} ]
        then
            echo "WARNING - Apache serves $req_psec Requests per second with an average CPU utilization of $cpu_load% since $uptime second
s. Amount of workers currently busy: $wkrs_busy, currently idle: $wkrs_idle! | $perfdata"
            exit $ST_WR
        elif [ ${req_psec} -ge ${crit_req} ]
        then
            echo "CRITICAL - Apache serves $req_psec Requests per second with an average CPU utilization of $cpu_load% since $uptime secon
ds. Amount of workers currently busy: $wkrs_busy, currently idle: $wkrs_idle! | $perfdata"
           exit $ST_CR
        else
            echo "OK - Apache serves $req_psec Requests per second with an average CPU utilization of $cpu_load% since $uptime seconds. Am
ount of workers currently busy: $wkrs_busy, currently idle: $wkrs_idle! | $perfdata"
            exit $ST_OK
        fi
    else
        echo "OK - Apache serves $req_psec Requests per second with an average CPU utilization of $cpu_load% since $uptime seconds. Amount
 of workers currently busy: $wkrs_busy, currently idle: $wkrs_idle! | $perfdata"
        exit $ST_OK
    fi
fi