https://exchange.nagios.org/directory/Plugins/Security/VPN-Software/check_openvpnas-2Esh/details

Uses sacli to get licensed connections, licence usage and checks for licence expiry. (LicUsage, VPNSummary or LICexpire) This check needs to be run locally via the check_by_ssh plugin. As a result, you will need to have ssh keys setup. This runs as user nagios on the OpenVPN AS server, but as sacli requires root to run, two lines are required in sudo to allow this:-

nagios ALL=(ALL) NOPASSWD: /usr/local/openvpn_as/scripts/sacli
nagios ALL=(ALL) NOPASSWD: /bin/grep

This check provides performance data to enable graph generation. It is written in bash.

#Check OpenVPN as parameters
define command {
        command_name    check_by_ssh-check_openvpnas
        command_line    /usr/lib/nagios/plugins/check_by_ssh -H $HOSTADDRESS$ -E -C "/home/nagios/checks/check_openvpnas.sh $ARG1$ "
}

#OpenVPN AS checks

define service{
        use                             generic-service
        host_name                       vpnserver1
        service_description             Check OpenvpnAS licence usage
        check_command                   check_by_ssh-check_openvpnas!LicUsage
        contact_groups                  vpnadmin
        }
define service{
        use                             generic-service
        host_name                       vpnserver1
        service_description             Check OpenvpnAS VPN usage
        check_command                   check_by_ssh-check_openvpnas!VPNSummary
        contact_groups                  vpnadmin
        }
define service{
        use                             generic-service
        host_name                       vpnserver1
        service_description             Check OpenvpnAS licence expiry
        check_command                   check_by_ssh-check_openvpnas!LICexpire
        contact_groups                  vpnadmin
        }

        

#!/bin/bash
# Written Andrew Stringer, 04/09/2014 contact me on:- nagios atsymbol rainsbrook dot co dot uk
#Name check_openvpnas.sh
 
# Purpose is to check OpenVPN Access Server status.
#Checks Licence status, number of connections and licence expiry dates.
 
#Print out command line options
usage() { echo "Usage:- check_openvpnas.sh <check-to-perform> (LicUsage, VPNSummary or LICexpire)" 1>&2; exit 4; }
 
#Check we have some arguments passed
if [ -z "$1" ] ; then
        usage
        exit 4
fi
 
#This requires an addition to the sudoers file:-
#nagios ALL=(ALL) NOPASSWD: /usr/local/openvpn_as/scripts/sacli
#nagios ALL=(ALL) NOPASSWD: /bin/grep
 
#sacli needs to be run as root because it can run auth type commands against openVPN
SACLI="sudo /usr/local/openvpn_as/scripts/sacli"
 
 
 
case $1 in                                                                                                                                                                                           
        LicUsage | licusage )                                                                                                                                                                        
                #LicUsage         -> show active connections compared to license limit (usage, limit)                                                                                                
                LIC=`${SACLI} LicUsage`                                                                                                                                                              
                #[ 30, 30 ]                                                                                                                                                                          
 
                LIC1=${LIC/[/}                                                                                                                                                                       
                #30, 30 ]                                                                                                                                                                            
 
                LIC2=${LIC1/]/}                                                                                                                                                                      
                #30, 30                                                                                                                                                                              
 
                LICINUSE=$(echo ${LIC2} | cut -f1 -d, )
                #echo "LICINUSE = ${LICINUSE}"
 
                TOTLIC=$(echo ${LIC2} | cut -f2 -d, )
                #echo "TOTLIC = ${TOTLIC}"
 
                LICFREE=$(( $TOTLIC-$LICINUSE ))
                #echo "LICFREE = ${LICFREE}"
 
 
                if  [[ "$LICFREE" -gt 4  ]]; then
                        STATUS=0
                        TEXT="OK. ${LICFREE} licences available.  | AvailableLicences=${LICFREE};4;2;"
                elif [[ "$LICFREE" -le 2  ]]; then
                        STATUS=2
                        TEXT="CRITICAL - ${TOTLIC} total, ${LICINUSE} in use, ${LICFREE} client licences available. | AvailableLicences=${LICFREE};4;2;"
                elif [[ "$LICFREE" -le 4 ]]; then
                        STATUS=1
                        TEXT="Warning - ${TOTLIC} total, ${LICINUSE} in use, ${LICFREE} client licences avilable. | AvailableLicences=${LICFREE};4;2;"
                else
                        STATUS=3
                        TEXT="Licence state unknown."
                fi      ;;
 
 
        VPNSummary | vpnsummary )
                VPNSUMMARY=`${SACLI} VPNSummary`
                #{  "n_clients": 26 }
                #echo "$VPNSUMMARY"
 
                VPNSUMMARY1=`echo $VPNSUMMARY | cut -f2 -d:`
                #echo "$VPNSUMMARY1"
                # 26 }
 
                VPNSUMMARY2=${VPNSUMMARY1/\}/}
                #echo "$VPNSUMMARY2"
                #> 26 <
                STATUS=0
                TEXT="${VPNSUMMARY2} VPN clients connected.  | VPN Clients Connected=${VPNSUMMARY2}" ;;
 
        LICexpire | licexpire )
 
                MINLICDAYS=1000000
                MINLICNAME=''
                STATUS=''
 
                #Get today in seconds
                TODAY=`date +%s`
 
                LICLOC='/usr/local/openvpn_as/etc/licenses'
                #LICLOC='/tmp/licence/'
 
                for LIC in `ls -1 ${LICLOC}`
                do
                        LICNAME=${LIC}
 
                        LICEXPIRETMP=`sudo grep 'expiry_date=' ${LICLOC}/${LICNAME}`
 
                        #Expires expiry_date=20150821
                        LICEXPIRE=`echo $LICEXPIRETMP | cut -d= -f2`
 
                        if [[ $LICEXPIRE == '' ]]; then
                                EX=none
                                #echo "No expiry in ${LICNAME}"
                        else
                                #echo "${LICNAME} expires ${LICEXPIRE}"
                                #Work out the difference in seconds between expiry date and now
                                EXP1=$(( `date -d ${LICEXPIRE} +%s` - ${TODAY} ))
 
                                #Convert to days - 60x60x24
                                EXP2=$(( ${EXP1} / 86400 ))
 
                                if [[ $EXP2 -lt 0 ]]; then
                                        STATUSTXT='Warning!! Check for expired licence files.'
 
                                elif [[ $EXP2 -lt $MINLICDAYS ]]; then
                                        MINLICDAYS=$EXP2
                                        MINLICNAME=$LICNAME
 
 
                                fi
                        fi
 
                done
 
                #echo "Next licence >$MINLICNAME< expires in >$MINLICDAYS< days. ${STATUSTXT}"
 
                if  [[ "$MINLICDAYS" -gt 31  ]]; then
                        STATUS=0
                        TEXT="OK. No licence expiry in next 31 days. ${STATUSTXT} | ${MINLICNAME} Expires in = ${MINLICDAYS}Days;31;4;"
                elif [[ "$MINLICDAYS" -le 31  ]]; then
                        STATUS=1
                        TEXT="WARNING - Next licence >$MINLICNAME< expires in >$MINLICDAYS< days. ${STATUSTXT} | ${MINLICNAME} Expires in = ${MINLICDAYS}Days;31;4;"
                elif [[ "MINLICDAYS" -le 7 ]]; then
                        STATUS=2
                        TEXT="CRITICAL - Less than 1 week before >$MINLICNAME< expires! ${STATUSTXT} | ${MINLICNAME} Expires in = ${MINLICDAYS}Days;31;4;"
                else
                        STATUS=3
                        TEXT="Licence expiry state unknown."
                fi      ;;
 
 
 
 
        *)
                echo "Please specify LicUsage, VPNSummary or LICexpire" ;;
 
esac
 
 
 
 
 
if [[ $STATUS -eq 0 ]]; then
        echo "${TEXT}"
        exit 0
elif [[ $STATUS -eq 1 ]]; then
        echo "${TEXT}"
        exit 1
elif [[ $STATUS -eq 2 ]]; then
        echo "${TEXT}"
        exit 2
else
        echo "${TEXT}"
        exit 3
fi
 
exit 0