Setup MRTG to monitor QoS Policies
NOTE: investigate “snmp mib persistant” command on IOS.
here is a “how to” for monitoring QoS with MRTG:
Firstly of course, install MRTG on system (follow instructions www.mrtg.org)
Do a snmpwalk of ifDescr to get all interfaces:
– Make note of the number following ifDescr.xx for the interface that is desired to be monitored.
Do a snmpwalk of cbQoSIfIndex (oid = 1.3.6.1.4.1.9.9.166.1.1.1.1.4) to get the list of ‘logical’ interface for which a policy map is assigned.
Example: a Serial interface 5/2:0 mapped to 1549:
IF-MIB::ifDescr.16 = Serial5/2:0
SNMPv2-SMI::enterprises.9.9.166.1.1.1.1.4.1549 = 1
Do a snmpwalk of cbQoSCMCfgEntry (oid = 1.3.6.1.4.1.9.9.166.1.7.1.1) to get the arbitrary numbers that are assigned to the configured class-maps on the router.
Do a snmpwalk of cbQosConfigIndex (oid=1.3.6.1.4.1.9.9.166.1.5.1.1.2). This will return the arbitrary number combination of the interface ID and the Class map.
NOTE: This generates a long list, so maybe pipe this toa text file, enabling easy searching.
Continuing this example, to find the OID to watch with MRTG, to monitor the CM-Scavenger class map on Serial 5/2:0, would want to scroll in the text file to the lines starting with: .1.3.6.1.4.1.9.9.166.1.5.1.1.2.1549.xxxx = yyyy
Then look for a yyyy value of 1091
From above example:
.1.3.6.1.4.1.9.9.166.1.5.1.1.2.1549.1613 = 1091
The OID is that would be added into the MRTG Configuration file.
.1.3.6.1.4.1.9.9.166.1.15.1.1.11.1549.1613
The last 2 values in the oid are taken from the previous snmpwalk
Example of MRTG Configuration file for example above:
EnableIPv6: no
WorkDir: /var/www/html/mrtg/test
Options[_]: bits,growright
RunAsDaemon: Yes
######################################################
# Utilisation report for 10.31.254.253
######################################################
Target[Default]:1.3.6.1.4.1.9.9.166.1.15.1.1.11.1549.1613&1.3.6.1.4.1.9.9.166.1.15.1.1.11.1549.1613:public@127.0.0.1
MaxBytes[default]: 100
LegendI[default]: In
LegendO[default]: Out
Title[default]: Scavenger Utilization report for 127.0.0.1
Background[default]: #FFFFFF
PageTop[default]: <h1><B> Scavenger Utilization Class Usage Analysis for 127.0.0.1 Interface 5/2:0</b></h1>
<br><font face=’Arial’ size=2>Link Description : Serial 5/2:0
<br><font face=’Arial’ size=2>Device : 127.0.0.1
<br><font face=’Arial’ size=2>Speed : T1
<br><font face=’Arial’ size=2>System Location :
<br><font face=’Arial’ size=2>System Description:
