librenms-plugin-cisco-pppoe
A LibreNMS v2 plugin that brings PPPoE sessions from Cisco BRASes into your monitoring over SNMP.
What it solves
LibreNMS reads CPU, memory, port traffic and temperatures from Cisco ASR1000s, but it says nothing about PPPoE termination. That’s the number I actually need: how many sessions sit on which BRAS.
The plugin reads it straight from CISCO-PPPOE-MIB and CISCO-SUBSCRIBER-SESSION-MIB and puts it on a single page.
What it shows
- an overview of every BRAS with total sessions, the PTA / FWDED / TRANS breakdown and utilisation against the limit,
- a device detail with sessions per interface, idle sub-interfaces hidden automatically,
- a subscriber list with username, state and assigned IP address,
- a panel on the LibreNMS device page, linking to the graph.
How it’s built
It’s a native LibreNMS v2 plugin, so no fork and no core patches. You install it by cloning into app/Plugins/ and enabling it in the UI.
All queries use numeric OIDs, so there are no MIB files to ship into the installation. Results are cached, and the subscriber list is only fetched on demand so the BRAS doesn’t take a multi-thousand-row walk on every page load.
The plugin keeps no history of its own. Instead, one button registers the session count as a Custom OID on every matching BRAS, leaving graphing and alerting to the LibreNMS poller.
Tested on
LibreNMS 26.8.2, Cisco ASR1000 running IOS-XE 15.5(3)S. MIT licensed.
For the full story of how it came about and what I got wrong on the way, see the post PPPoE sessions from Cisco ASR1000 in LibreNMS.