After setting up my apartment’s OpenBSD based network, I decided it would be handy to have a simple report generator to describe active DHCPD leases. I also wanted to brush up on Perl a bit. This Perl script is the natural result of such circumstances.
Run dhcpd-report.pl to generate a plaintext or HTML report of current leases in the DHCPD lease database and reservations in dhcpd.conf. In my usage, I have the script set to run once every five minutes in a cron job, sending output to an HTML file in a web server document root. (On OpenBSD, httpd runs in a chroot jail; if I were to run this script as CGI it wouldn’t have direct access to the DHCPD configuration files.) Thus the script can be used to give you a reasonably up to date web page displaying your network’s DHCP clients.
By default, the program looks for dhcpd.leases and dhcpd.conf in /var/db/ and /etc/, respectively, which are these files’ locations in OpenBSD 4.1. If needed, you can change where the script looks for these files by modifying a pair of constants near the top of the main program.
*Sort of like an ATM machine or a PIN number…