nagios ssh Plugin

#!/bin/bash
#### NO SSH CONNECTION 1FUNCATION AND SSH HAI TO 2FUNCATION RUN.
# Check for missing parameters
if [[ -z "$1" ]] || [[ -z "$2" ]] || [[ -z "$3" ]] || [[ -z "$4" ]]; then
        echo "Missing parameters! Syntax: ./check_ssh.sh <HOSTNAME> <PORT_NO> <WARNING_THRESHOLD> <CRITICAL_THRESHOLD>"
        exit 2
fi

host=$1
port=$2
Warning=$3
Critical=$4

########### check Port ############################################
netstatus=$(netstat -nlp | grep :$port)

if [[ $? == 1 ]]; then
       echo "CRITICAL - PORT NOT ESTABLISHED"
        exit 2
fi
############ ESTABLISHED connection ###############################
command=$(netstat -alntp | grep :$port | grep ESTABLISHED | awk '{print $5}' | cut -d ":" -f1 | sort |uniq)
check_command=$(echo $command | wc -l)

if [[ $command = "" ]];then
 echo "OK - ESTABLISHED"
 exit 0
fi

if [ -f /tmp/.user_count ];then
$(rm -rf /tmp/.user_count)
fi
######### looping ############################
if [ $check_command -gt 0 ];then
loop_ip=$(for ip in $command;
do
command1=$(who | grep $ip | awk {'print $1'})
com=$(who | grep $ip | awk {'print $1'} >> /tmp/.user_count)
echo -e "$(echo $command1) $ip"
done)

fi
##############################################
if [ -f /tmp/.user_count ];then
count=$(wc -l < /tmp/.user_count)
fi
# Connection is Establish---OK;

if [[ "$count"<="$Warning" ]]; then
        echo "OK - ESTABLISHED/Total_user $count "
        echo "$loop_ip"
        exit 0
fi

# Connection is WARNING---WARNING;

if [[ "$count"=>"$Warning" ]] && [[ "$count"<="$Critical" ]]; then
        echo "WARNING - ESTABLISHED/Total_user $count"
        echo "$loop_ip "
        exit 1
fi

# Connection is CRITICAL---CRITICAL;

if [[ "$count"=>"$Critical" ]]; then
       echo "CRITICAL - ESTABLISHED/Total_user $count"      
        echo "$loop_ip "
        exit 2
fi
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./check_ssh.sh localhost 22 4 5