Skip to content

ISC DHCP Stats

A small python3 script that reports current DHCP leases stats and pool usage of ISC DHCP Server.

Also you have to install the dhcpd-pools and the required Perl modules.

Install prerequisites

apt install cpanminus libmime-base64-perl libfile-slurp-perl
cpanm Net::ISC::DHCPd::Leases

pkg install p5-JSON p5-MIME-Base64 p5-App-cpanminus p5-File-Slurp
cpanm Net::ISC::DHCPd::Leases

cpanm Net::ISC::DHCPd::Leases MIME::Base64 File::Slurp

SNMP Extend

  1. Copy the shell script to the desired host.

    wget https://github.com/librenms/librenms-agent/raw/master/snmp/dhcp -O /etc/snmp/dhcp

  2. Make the script executable

    chmod +x /etc/snmp/dhcp

  3. Edit your snmpd.conf file On a slow system, run the script from cron.

    edit (usually /etc/snmp/snmpd.conf) and add:

    extend dhcpstats /etc/snmp/dhcp -z

    edit (usually /etc/snmp/snmpd.conf) and add:

    extend dhcpstats /etc/snmp/dhcp -Z -w /var/cache/dhcp_extend

    Setup cronjob to run every 5 minutes. add the following to cron \etc/crontab.d/librenms_dhcp:

    */5 * * * * /etc/snmp/dhcp -Z -w /var/cache/dhcp_extend

    The following options are also supported.

    Option Description
    -c $file Path to dhcpd.conf.
    -l $file Path to lease file.
    -Z Enable GZip+Base64 compression.
    -d Do not de-dup.
    -w $file File to write it out to.

  4. Restart snmpd on your host

    LibreNMS discovers the application automatically, as described at the top of the page. If the discovery fails, do the steps under the SNMP Extend heading at the top of the page.