ISC dhcpd lease analysis and reporting

This is dhcpd-pools ISC dhcp shared network and pool range usage analysis. Purpose of command is to count usage ratio of each IP range and shared network pool which ISC dhcpd is in control of. Users of the command are most likely ISPs and other organizations that have large IP space.

Program is written C. Design goal is to get analysis done quickly where there is lots of data. On cheap laptop the speed of analysis is more than 100k leases per second. Number of ranges, or shared networks, does not make any significant difference in getting analysis done.

Is dhcpd-pools still developed?

In short no, it is not.

ISC DHCPD has reached EOL. Users are Kea DHCP server instead. Kea has native statistics, so it does not require this tool and therefore the dhcpd-pools is obsolte.

Where I can get dhcpd-pools?

Download release package or clone from git. Build instructions are in README file.

See also SourceForge project page.

The last release v3.3

$ sha256sum ./dhcpd-pools*tar*
a414e0b8061c2cba4685aff565623bcb9992699d7290a17c9f7014abe140c689  ./dhcpd-pools-3.3.tar.xz
20b52dd9058115b8e2c68c496dda6793118aa245e18e17146f1a7479bb5f689e  ./dhcpd-pools-3.3.tar.xz.asc

$ sha512sum ./dhcpd-pools*tar*
9ae1199883aaa90839999e609049c50c0d8cfc58f5e7370c3569af9bf9e281d096664db1982294d602559038f6456021eec32147c7325b2891af13d7be4e9e69  ./dhcpd-pools-3.3.tar.xz
a5624327064da567b6017826402e83ef00ec74668735f21fc342ef0fcc9541fe386f490df0e13af28d9e2f87b1e4342f3afb23c17451b5a75ef90bd6be2845d2  ./dhcpd-pools-3.3.tar.xz.asc

$ gpg --verify ./dhcpd-pools-3.3.tar.xz.asc ./dhcpd-pools-3.3.tar.xz
gpg: Signature made Mon 28 Apr 2025 14:49:48 BST
gpg:                using RSA key 8ED396E37E38D471A00530D3A9553245FDE9B739
gpg: Good signature from "Sami Kerola (https://www.iki.fi/kerolasa/) " [ultimate]

Documentation

The dhcpd-pools manual page, and Doxygen software reference documentation are available online.

Getting the output you need

1. Start with:
   dhcpd-pools --config=path --leases=path --color=always --format=text
2. Play with options and see how output changes. Options to try:
   --all-as-shared --crit-count --critical --minsize --snet-alarms --warn-count --warning
3. Start filtering output. Options to try:
   --skip --limit
4. Change --format option to what you need, and maybe include --perfdata if you want nagios alarm format.
5. Done.

Reference information

The program was written because DHCPStatus, DHCP Usage Statistics, reportdhcp.pl, lease_analyzer and dhcpd-snmp where too slow to handle huge number of leases. There is also difference in printed details. The dhcpd-pools does not print quite as much information as some other tools.

Notice that this utility is not the same as dhcpd-pool that is maintained by Trond Hasle Amundsen.

Just for laugh, obsolete awk proof of concept (version 1.4) dhcpd-pools.awk

Where to send questions, bug reports, code contributions...

Sami Kerola <kerolasa@iki.fi>