Utilizzare i nomi SNMP delle Interfacce di un Router in Nprobe

Con script automatico

Se si aggiungono tutti i router monitorati come device SNMP, questo script ne estrae gli ip, e popola il file snmp_mappings.txt

cat > /usr/local/sbin/make_snmp_mappings.sh <<'EOFile'
#!/bin/bash

COMMUNITY=$1
NEW_DEV_DETECTED="1"

if [ -z "$COMMUNITY" ]
then
	echo "Usage: $0 snmp_community_name"
	exit 127
fi

IPS=$(redis-cli -h 127.0.0.1 --scan --pattern '*' | grep snmp| grep system | cut -f 2-5 --delimiter='.')
if [ -f /etc/nprobe/snmp_mappings.txt ]
then
	/bin/mv -f /etc/nprobe/snmp_mappings.txt /etc/nprobe/snmp_mappings.txt.old
fi

for IP in $IPS
do
        echo "Adding $IP"
        /usr/bin/build_snmp_mappings.sh $IP 2c ${COMMUNITY} >> /etc/nprobe/snmp_mappings.txt
done

if [ -f /etc/nprobe/snmp_mappings.txt.old ]
then
	diff -q /etc/nprobe/snmp_mappings.txt /etc/nprobe/snmp_mappings.txt.old
	NEW_DEV_DETECTED="$?"

fi

if [ $NEW_DEV_DETECTED -eq "1" ]
then
        echo "New device detected. Restart Nprobe"
        #echo "New device detected. Restart Ntop and Nprobe"
        #systemctl restart ntopng.service
        for UNIT in $(systemctl list-units nprobe\* --all | grep nprobe | grep '\.service' | tr -s ' '  | cut -f 2 --delimiter=' ')
        do
                systemctl restart $UNIT
        done
else
        echo "No new devices detected"
fi
EOFile

chmod +x /usr/local/sbin/make_snmp_mappings.sh

Impostare la community:

export COMMUNITY="public"

Prepare il cronjob

if [ -n "$COMMUNITY" ]; then echo "# Check for new SNMP deviced and map them every 5 minutes" > /etc/cron.d/ntopngSnmpMappings; echo "/5 * * * * root /usr/local/sbin/make_snmp_mappings.sh ${COMMUNITY} >  /dev/null" >> /etc/cron.d/ntopngSnmpMappings; else echo -e "\nDEFINE COMMUNITY first with export COMMUNITY=\"snmp_communit_name\".\nCRONJOB NOT ENABLED ! \n"; fi

Lanciare il comando manualmente due volte per testartlo

/usr/local/sbin/make_snmp_mappings.sh $COMMUNITY

• Lanciare poi nprobe con il parametro aggiuntivo

vi /etc/nprobe/nprobe-test.conf

###
--snmp-mappings /etc/nprobe/snmp_mappings.txt
###

• Riavviare nprobe:

 systemctl restart nprobe@test.service 

• Nella webgui appaiono i nomi delle interfacce

Manualmente

• Per ogni router, occorre generare il file di testo che contiene i nomi:

/usr/bin/build_snmp_mappings.sh 192.168.253.254 2c public > /etc/nprobe/snmp_mappings.txt

Il contenuto sarà del tipo

192.168.253.254 1 "vtnet0"
192.168.253.254 2 "vtnet1"
192.168.253.254 3 "vtnet2"
192.168.253.254 4 "enc0"
192.168.253.254 5 "lo0"
192.168.253.254 6 "pfsync0"
192.168.253.254 7 "pflog0"
192.168.253.254 8 "ovpns1"
192.168.253.254 9 "ovpns2"
192.168.253.254 10 "ovpns3"
192.168.253.254 11 "ovpns4"

• Lanciare poi nprobe con il parametro aggiuntivo

vi /etc/nprobe/nprobe-test.conf

###
--snmp-mappings /etc/nprobe/snmp_mappings.txt
###

• Riavviare nprobe:

 systemctl restart nprobe@test.service 

• Nella webgui appaiono i nomi delle interfacce

Riferimenti

• Tuning nProbe Performance — nProbe 10.1 documentation