Wireless Access

I'm trying to figure out the best method for setting a trigger for when a subset of APs (already in isolated folder) change channels. I was thinking of keying off an SNMP trap for channel changes by looking for a Device Event with the contents "ChannelChange", however that is not working.

 

Any ideas on how to do this successfully?

 

That seems the logical way to setup this trigger.    Is the Device Event you are looking for being sent to AirWave and it is just triggering?

 

 

I can't easily answer whether the trap is arriving in Airwave. Looking at one of our 4 Airwave servers, I see there are 13+ million traps, and with that many, I can't search through the messages for any string (e.g., ChannelChange).

 

What I'm hoping for is someone that has implemented something similar. Have you done anything like this before, clembo?

The trap is wlsxChannelChanged.   For starters, you can see if it is enabled on the controller using "show snmp trap-list".   

I have not setup this particular trigger before, but just went to do it in my lab setup.    I am running AMP 7.6.1 and for some reason the Device Event trigger for Event Contents only has "matches".  I thought in the past it had "contains" as an option in the dropdown.    Using "matches" does not work for any SNMP Trap.    I will try and upgrade to see if it adds "contains" back.

I'm not sure if that's the right trap. The MIB guide says that's deprecated. The wlsxNChannelChanged seems current, as does wlsxAPChannelChange . . . in either case, my device event trigger is looking for "ChannelChange", which should capture all those, correct? Let me know if you had success. - Ryan -

Yes, I think you are right about the proper traps.

 

Does your trigger say that the Event Content "matches" or "contains"?    I upgraded, and it still only has "matches".....which doesn't work.  I thought "contains" used to be an option at one time.   Other than that, I'd ask TAC if they have any suggestions on capturing that trap/trigger.    Please post if you are successful for future consideration.

Thanks

Woah! Didn't notice that before, but like yours, mine says "matches". Yeah, that won't work unless there's built-in logic to the "Event Content", which understands to look for an Event that contains what you specify. I guess I have no choice but to open another case . . . which will be #12 that I have open right now. - Ryan -

Is there a reason you're looking for this as a trigger?  If you don't need instantaneous information, you can get the count of channel changes in the RF Health report.

@rgin,  what is the proper method to create any trigger based off an SNMP trap event contents?    When creating the trigger, there is not the option to choose Event Contents "contains"; just "matches".    Is there a recommended approach to matching a portion of an SNMP event to force a trigger?

@clembo, I got this working. It seems the "matches" component is not saying that the ENTIRE event contents have to match what you specify. Rather, just match what you type when you looking through the entire event's contents. @rgin, trigger is necessary to allow us to know immediately that the channel has changed so we can take specific actions.

Ryan, what did you "match"  to get it to work?

"ChannelChange". It picked up on wlsxAPChannelChange trap, so you could be more specific if you want. I'm matching on that and then another match on part of the AP name in order to check channel changes for a building. - Ryan -