Cisco Class-based QoS discovery and collection plugin

Status: Released; Last modified: 03-MAY-2004


DiffServ-based quality of service is being deployed in many networks these days, and the choice of management systems able to monitor QoS parameters is too narrow.

Cisco IOS provides QoS statistics in its CISCO-CLASS-BASED-QOS-MIB. This MIB is far too complex for a regular SNMP collector.

The cbqos Torrus plugin provides a complete solution for automated SNMP discovery and collection for QoS objects on Cisco routers. It is the first open source solution of this kind.

Other existing tools for QoS monitoring are:


Follow the Torrus installation guide for the main software installation.

Unpack the plugin distribution package in some directory:

  gzip -dc tp-cisco-cbqos-1.X.tar.gz | tar xvf -

Then run the Torrus plugin installation utility:

  torrus install_plugin tp-cisco-cbqos-1.X

Restart all Torrus processes, including Apache HTTP daemon.


Use your Torrus the usual way: devdiscover will automatically find QoS objects on your routers, compilexml will find the required templates, and collector will initialize all required tables and will start collecting data.

Note: QoS is a software feature, and there's no means to determine that the configuration has changed. You need to re-run devdiscover and compilexml whenever your QoS configuration changes. As usual, the collector will automatically detect the router reload or Torrus configuration change, and re-initialize its tables.

Tunable parameters

The following parameters may be specified in devdiscover input XML:

Implementation details

CISCO-CLASS-BASED-QOS-MIB uses complex indexing for statistics objects:

  1. cbQosPolicyIndex in cbQosServicePolicyTable is found by matching 6 values: cbQosIfType, cbQosPolicyDirection, cbQosIfIndex, cbQosFrDLCI, cbQosAtmVPI, cbQosAtmVCI

  2. Use cbQosPolicyIndex to access the cbQosObjectsTable, and find the cbQosObjectsIndex and cbQosConfigIndex assigned to the QoS feature.

  3. Use cbQosConfigIndex to access configuration tables (cbQosxxxCfgTable) for information about the feature.

  4. Use cbQosPolicyIndex and cbQosObjectsIndex to access QoS statistics tables (cbQosxxxStatsTable) for information about the QoS feature.

The plugin introduces a special Torrus collector type, ``cisco-cbqos''.

Each Torrus datasource is identified by Service Policy, QoS Feature, and associated SNMP objects type.

The following parameters identify the Service Policy:

 cbqos-direction =>
 cbqos-interface-name (mapping to IF-MIB interface index)
 cbqos-interface-type =>
   "frDLCI" =>
   "atmPVC" =>

The following parameters identify the QoS Feature:

 cbqos-object-type =>
   "classmap" =>
   "matchStatement" =>
   "queueing" =>
   "trafficShaping" =>
   "police" =>

SNMP objects are defined in regular Torrus XML templates. Collector substitutes POL and OBJ strings in snmp-object parameter with the current values of policy and object index correspondingly.

Development of this plugin was sponsored by Cablecom GmbH.


Copyright (c) 2004 Stanislav Sinyagin <>