Wi-Fi clients events are blocked, as device generating high rate of events.

Anyone know what is this alarm that shows CnMaestro?

Thanks

This alarm is triggered if cnMaestro recieved a large volumn of Wi-Fi Client Connected/Disconnected events in a short period of time.  While the alarm is active, these types of events are ignored in order to prevent flooding the system.  There is a cool down period, after which the alarm is automatically cleared and events are then processed normally.

How can one find the problematic client? As this is causing network drops on my wifi network.

Check the Events tab of that device for client connect/disconnect events.  Events leaking up to the blocking alarm being activated are still logged.  The threshold for activating this alarm is 50 events within 5 minutes per client.

The "Device events are blocked, as device generating high rate of events." alarm is a device level block and is triggered by 200 events within 5 minutes.  For this alarm, check the logs on the device web UI.

If you are running On-Premises you can generate a client's session report for the blocked device to see the number of sessions generated each minute.

Dear Jordan,

Dear Readers,

We have this "Wi-Fi clients events are blocked"-problem, too.

In our school we have 44 APs (42*e410 + 2*e600), we have 800 pupils (with probably 800 smartphones:) and 80 employees.

We have 4 WLANs and 3 Guest Portals
WLAN1 for school-owned devices with MAC Authentication (No Guest Portal)

WLAN2 for employees with Guest Portal "Employee", vouchers are valid 365 days

WLAN3 for single guest with one device with a Guest Portal for "SingleGuest", vouchers are valid 90 Minutes

WLAN4 for group with 16 devices (group of pupils), vouchers are valid 90 Minutes

All WLANs are open and the Guest Portals are well configured and worked fine for 4 months.

Now it is the second time, the whole Guest Portals broke down. One or two days before the "Major Alarms" reported the "Wi-Fi clients events are blocked, as device generating high rate of events."

I made a ticket with the support, they fixed something in the Portal and it was ok for one week, but now it¬īs here again.

Can you try to estimate the following:

Maybe this Alarms occurs when 800 Children are coming to school in the morning. As you described the Alarm occurs if cnMaestro recieved "a large volume of WiFi Clients Connect/Diconnect in a short time period"

But how can I fix this? It is a normal Situation in a school, a congress Hall, a station etc...The system must work with a huge volume of devices (256 per AP! as cambium decribes)

Could it help to switch the security from "open" to WPA2? (Actually we wanted an easy-to-use-system: open signal, guest-portal with an voucher, done.

I would be glad if somebody can help me.

Greetings Arnd

Hi Arnd,

The alarm itself isn't necessarily a problem.  It is activated to notify you that events sent by the device are temporarily not being logged.  The device itself should continue operating normally.  The Guest Portal breaking down should be investigated as its own issue.  I recommend contacting customer support again.

The Wi-Fi client events are blocked alarm activate after 50 connect/disconnect events are recieved within 5 minutes for a single client.  What does the Events tab look like in the minutes leading up to this alarm activating?  A single phone or laptop connecting/disconnecting very rapidly does not sound like normal behavior.  It is possible that is is related and can be used as data surrounding the time when the Guest Portal goes down.

Is there a way to up this threshold? For CnMaestro on premises?

Currently this is not configurable.  I have forwarded this request for consideration.  The thresholds have been set up for performance reasons.

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we also facing this problem , any one give solution, in a same network one device connected and another device connect but no internet , i checked all basic network but problem is still there

We are also starting to see this issue. 

can we get this FIXES ASAP? No point for cambium introducing this security features but putting cambium reputation of wifi stability and connectivity at risk.

We are experiencing this also. It would help us to troubleshoot if we knew the root cause--i.e., is it a hacker trying to shut down the network with a special software, a DHCP problem, a bad client NIC problem? When I opened a ticket I was just told what we've read in this post, but I need to understand the mechanics of how the device generates this "high rate" of events to possibly pinpoint a client device and blacklist it.

We have multiple cases on this.

Its very disturbing, from what i know about the alarm that its tell user is using too much bandwidth or visit spam site or etc. 

Can Cambium explain what the use of this alarm?

What do we do if we found this kinda of alarm, we need some kind of information to tell to our customer. 

Does it automatically kick user from SSID/ from using the internet? 

this alarm will not cause any impact on client wireless connectivity or data transfer. this is an indication in cnMaestro that it is rate limiting these events 

Hi Jordan,

Like everyone else on this thread, I'm also experiencing this Wi-Fi clients events blocked alarm. In your previous response you indicated that this alarm is caused by a SINGLE client which is rapidly connecting/disconnecting. The big question is how do I troublshoot which client is causing this event? I can't see any indications on the event itself... it only gives the MAC address of the cnPilot E-410 that is complaining. In poking around cnMaestro, I don't find anywhere that I can see the root cause of this event.

Also, my alarm/event log is packed with hundreds of these alarms/events. How can I clear the logs so I can make some sense of them? I don't see any way to clear everything out.

One last question that may or may not be related... all of the clients on the system complain of VERY long times to connect to the APs. Indeed, when I go onsite with either my personal laptop or my iPhone, it literally can take up to 30 seconds for either of them to finally connect to the network, which seems unreasonable to me. How can I troubleshoot this as well? This long connection time may be causing clients to bail and restart the connection process, which may be causing the high events alarms.

Any help here would be appreciated. 

Thanks!

hi,

for the query "One last question that may or may not be related... all of the clients on the system complain of VERY long times to connect to the APs. Indeed, when I go onsite with either my personal laptop or my iPhone, it literally can take up to 30 seconds for either of them to finally connect to the network, which seems unreasonable to me. How can I troubleshoot this as well? This long connection time may be causing clients to bail and restart the connection process, which may be causing the high events alarms."

can you share cnPilot AP techdump for us (channareddy.ireddy@cambiumnetworks.com) to look into configuration and figure it out pssoible root cause for the issue.

i recommed to open up seprate post for this quey under cnPilot E-Series AP section. 

Any of you installed the AP’s through WIFI4EU project? I am also seeing this on a few sites. Maybe EU testing?

I have this same error reported on an e700 radio started Aug 2, 2019, the alarm has been active 173 days, is STILL active, yet eh AP has not had an active client in days. I have read and understand what cambium SAYS causes this alarm, however there are no clients to cause this alarm... so how is there an alarm and why is it still active?

Hello, is there any update on this topic? I am so much exaggerated with this issue. 

Using CnPilot E410 and E600

hi,

does ap deployed for public wi-fi hot spot where ssid is open?  how many concurrent clients we see on ap and also what is unqiue client counts in last 24 hours (we can get this information from ap dash board in cnMaestro). The reason i am asking the question is trying to understand client connection frequencies