Shell Script To Monitor Services Such As Web / Http, Ssh, Mail Server

gistfile1.sh

    #!/bin/bash
    # Shell script to monitor running services such as web/http, ssh, mail etc.
    # If service fails it will send an Email to ADMIN user
    # -------------------------------------------------------------------------
    # Copyright (c) 2006 nixCraft project <http://www.cyberciti.biz/fb/>
    # This script is licensed under GNU GPL version 2.0 or above
    # -------------------------------------------------------------------------
    # This script is part of nixCraft shell script collection (NSSC)
    # Visit http://bash.cyberciti.biz/ for more information.
    # ----------------------------------------------------------------------
    # See URL for more info
    # http://www.cyberciti.biz/tips/processing-the-delimited-files-using-cut-and-awk.html
    # ---------------------------------------------------
    # Last updated: Jun - 15 - 2009.
    ports="22 53 80 25"
     
    # service names as per above ports
    service="SSH DNS WEB MAIL"
     
    #Email id to send alert
    ADMINEMAIL="[email protected]"
     
    #Bin paths, set them according to your Linux distro
    NETSTAT=/bin/netstat
    MAIL=/usr/bin/mail
    LOGGER=/usr/bin/logger
    ID=/usr/bin/id
     
    # Red hat usr uncomment
    MAIL=/bin/mail
    LOGGER=/bin/logger
     
     
    #Counters, set defaults
    c=1
    status=""
    sendmail=0
     
    # set the following to 1, if you want message in /var/log/messages via a SYSLOG
    logtosyslog=0
     
    # Log file used to send an email
    LOG="/tmp/services.log.$$"
     
    # log message to screen and a log file
    log(){
    echo "$@"
    echo "$@" >> $LOG
    }
     
    # log message and stop script
    die(){
    echo "$@"
    exit 999
    }
     
    # Make sure only root can run it
    is_root(){
    local id=$($ID -u)
    [ $id -ne 0 ] && die "You must be root to run $0."
    }
    # Look out for all bins and create a log file
    init_script(){
    [ ! -x $MAIL ] && die "$MAIL command not found."
    [ ! -x $NETSTAT ] && die "$NETSTAT command not found."
    [ ! -x $LOGGER ] && die "$LOGGER command not found."
    [ ! -x $ID ] && die "$ID command not found."
    is_root
    >$LOG
    }
     
     
    # check for all running services and shoot an email if service is not running
    chk_services(){
    log "-------------------------------------------------------------"
    log "Running services status @ $(hostname) [ $(date) ]"
    log "-------------------------------------------------------------"
     
    # get open ports
    RPORTS=$($NETSTAT -tulpn -A inet | grep -vE '^Active|Proto' | grep 'LISTEN' | awk '{ print $4}' | cut -d: -f2 | sed '/^$/d' | sort -u)
     
    # okay let us compare them
    for t in $ports
    do
    sname=$(echo $service | cut -d' ' -f$c)
    echo -en " $sname\t\t\t : "
    echo -en " $sname\t\t\t : " >> $LOG
    for r in $RPORTS
    do
    if [ "$r" == "$t" ]
    then
    status="YES"	
    sendmail=1
    break
    fi
    done
    echo -n "$status"
    echo ""
    echo -n "$status" >>$LOG
    echo "" >>$LOG
    # Log to a syslog /var/log/messages?
    # This is useful if you have a dedicated syslog server
    [ $logtosyslog -eq 1 ] && $LOGGER "$sname service running : $status"
     
    # Update counters for next round
    c=$( expr $c + 1 )
    status="NO"
    done
    log "-------------------------------------------------------------"
    log "This is an automatically generated $(uname) service status notification by $0 script."
     
    if [ $sendmail -eq 1 ];
    then
    $MAIL -s "Service Down @ $(hostname)" $ADMINEMAIL < $LOG
    fi
    }
     
    ### main ###
    init_script
    chk_services
     
    ### remove a log file ###
    [ -f $LOG ] && /bin/rm -f $LOG