Optional OS Settings

This page documents settings that can be set in the os yaml files or in config.php. All settings listed here are optional. If they are not set, the global default will be used.

User override in config.php

Users can override these settings in their config.php.

For example, to set an alternate icon for ios:

$config['os']['ios']['icon'] = 'fuzzybunny';

Ignoring Sensors

It is possible to filter some sensors from the configuration:

Filter all 'current' sensors for Operating System 'vrp'.

$config['os']['vrp']['disabled_sensors']['current'] = true;

Filter all sensors with description matching regexp '/PEM Iout/' for Operating System iosxe.

$config['os']['iosxe']['disabled_sensors_regex'][] = '/PEM Iout/';

Filter all 'power' sensors with description matching regexp '/ Power [TR]x /' for Operating System iosxr.

$config['os']['iosxr']['disabled_sensors_regex']['power'][] = '/ Power [TR]x /';

Ignore all temperature sensors

$config['disabled_sensors']['temperature'] = true;

Filter all sensors matching with description regexp '/PEM Iout/'.

$config['disabled_sensors_regex'][] = '/PEM Iout/';

Ignoring Interfaces

These settings are merged with the global settings, so you can only undo global ones with good_if

empty_ifdescr: false # allow empty ifDescr
bad_if: # ifDescr (substring, case insensitive)
    - lp0
bad_if_regexp: # ifDescr (regex, case insensitive)
    - "/^ng[0-9]+$/"
bad_ifname_regexp: # ifName (regex, case insensitive)
    - "/^xdsl_channel /"
bad_ifalias_regexp: # ifAlias (regex, case insensitive)
    - "/^vlan/"
bad_iftype: # ifType (substring)
    - sonet
good_if: # ignore all other bad_if settings ifDescr (substring, case insensitive)
    - virtual
bad_ifoperstatus # IfOperStatus (substring, case insensitive)
    - notPresent

Controlling interface labels

By default we use ifDescr to label ports/interfaces. Setting either ifname or ifalias will override that. Only set one of these. ifAlias is user supplied. ifindex will append the ifindex to the port label.

ifname: true
ifalias: true

ifindex: true

Poller and Discovery Modules

The various discovery and poller modules can be enabled or disabled per OS. The defaults are usually reasonable, so likely you won't want to change more than a few. These modules can be enabled or disabled per-device in the webui and per os or globally in config.php. Usually, a poller module will not work if it's corresponding discovery module is not enabled.

You should avoid setting these to false in the OS definitions unless it has a significant negative impact on polling. Setting modules in the definition reduces user control of modules.

poller_modules:
    bgp-peers: true
discovery_modules:
    arp-table: false

SNMP Settings

Disable snmpbulkwalk

Some devices have buggy snmp implementations and don't respond well to the more efficient snmpbulkwalk. To disable snmpbulkwalk and only use snmpwalk for an OS set the following.

snmp_bulk: false

If only some specific OIDs fail with snmpbulkwalk. You can disable just those OIDs. This needs to match exactly the OID being walked by LibreNMS. MIB::oid is preferred to prevent name collisions.

oids:
    no_bulk:
        - UCD-SNMP-MIB::laLoadInt

Limit the oids per snmpget

snmp_max_oid: 8