For the majority of our customers I install Cisco Prime Infrastructure as “enhanced” monitoring tool for the wireless infrastructure. I say “enhanced” because the WLC itself does have a few monitoring features, but all of those are “real time” and not for historical purpose.

However, not all the customers need the features that Prime Infrastructure has to offer or they already have some “basic” network monitoring in place. In those cases it is sometimes handy to add the WLC in that monitoring, which is most of the times SNMP based.

There is always one question when it comes to SNMP; “what OID do I have to use to get information X?”. I wanted to monitor the total number of associated clients on a particular WLC, but found out that it is very hard to find the right OID for doing so. There is some Cisco documentation about SNMP monitoring on a WLC but thats more “advanced” monitoring.

It turned out to be OID .1.3.6.1.4.1.9.9.618.1.8.12.0 which returns the value as a “gauge”, if you also want to monitor the number of joined AP’s you can use OID .1.3.6.1.4.1.9.9.618.1.8.4.0. There you go! 🙂