"...detects radar burst on radio..." causing really bad throughput

HI Johan, 

We also saw radar detections frequently on ZF7982 and R500.
This behaviour was in buildings with multiple floors and multiple APs hearing each other, together with a lot of wifi clients present. Outside business hours, there were no radar detection.
These were clearly false positives.  
The APs interpreted certain type of RF energy as radar pulse and triggered radar detection. 
Other vendors have/had this issue too. 

What to do?

- upgrade your ZD and test:
check the latest release notes for 10.x:
https://support.ruckuswireless.com/documents/1975-zonedirector-10-0-mr1-release-notes?_ga=2.15628790...
"Resolved Issues in Build 10.0.0.0.1424: Resolved a false radar detection issue for 7982 and R500 APs. "

- open a case 
- use 20MHz wide channels for channel reuse
- use non-DFS channels as a workaround

Cheers, 
Alex

Hi Alex,

Thank you very much for your feedback. It makes sense since we are talking about quite a large factory building with lots of APs.

It is a little strange that this problem (which I have noticed earlier but not to the same extend) suddenly arose this morning. One change I actually did yesterday was that I added one AP to the network...

Recommended firmware seems still to be 9.13.3.0.121. Is it really advisable to go for the 10.0.0.0.1424 version?

Best regards
Johan Axelsson

@Johan, 

I just provided several options in my first reply.
You should still ask support for advice. I did not try the 10.x.
If you have the possibility to test it, go for the latest MR1 10.0.1.0.17, not for the GA.

From "AP Activities" this morning:

Oct 19 08:34:55 EFGZD01 syslog: eventd_to_syslog():AP[[email protected]:68:4d:28:07:70] detects interference on radio [11a/n] and switches from channel [116] to channel [36]. 
Oct 19 08:34:38 EFGZD01 syslog: eventd_to_syslog():AP[[email protected]:68:4d:28:07:70] detects radar burst on radio [11a/n/ac] and channel [128] goes into non-occupancy period. 
Oct 19 08:34:38 EFGZD01 syslog: eventd_to_syslog():AP[[email protected]:68:4d:28:07:70] detects radar burst on radio [11a/n/ac] and channel [124] goes into non-occupancy period. 
Oct 19 08:34:38 EFGZD01 syslog: eventd_to_syslog():AP[[email protected]:68:4d:28:07:70] detects radar burst on radio [11a/n/ac] and channel [120] goes into non-occupancy period. 
Oct 19 08:34:38 EFGZD01 syslog: eventd_to_syslog():AP[[email protected]:68:4d:28:07:70] detects radar burst on radio [11a/n/ac] and channel [116] goes into non-occupancy period. 
Oct 19 08:32:12 EFGZD01 syslog: eventd_to_syslog():AP[[email protected]:68:4d:29:2b:10] detects interference on radio [11g/n] and switches from channel [11] to channel [1]. 
Oct 19 08:31:58 EFGZD01 syslog: eventd_to_syslog():AP[[email protected]:68:4d:28:07:70] detects interference on radio [11g/n] and switches from channel [11] to channel [6]. 
Oct 19 08:31:49 EFGZD01 syslog: eventd_to_syslog():AP[[email protected]:10:7f:25:16:70] detects interference on radio [11g/n] and switches from channel [11] to channel [6]. 
Oct 19 08:31:49 EFGZD01 syslog: eventd_to_syslog():AP[[email protected]:68:4d:29:2b:10] detects interference on radio [11a/n/ac] and switches from channel [100] to channel [104]. 
Oct 19 08:31:49 EFGZD01 syslog: eventd_to_syslog():AP[[email protected]:68:4d:28:07:70] detects interference on radio [11a/n/ac] and switches from channel [100] to channel [116]. 
Oct 19 08:31:31 EFGZD01 syslog: eventd_to_syslog():AP[[email protected]:68:4d:28:07:70] detects radar burst on radio [11a/n/ac] and channel [112] goes into non-occupancy period. 
Oct 19 08:31:31 EFGZD01 syslog: eventd_to_syslog():AP[[email protected]:68:4d:28:07:70] detects radar burst on radio [11a/n/ac] and channel [108] goes into non-occupancy period. 
Oct 19 08:31:31 EFGZD01 syslog: eventd_to_syslog():AP[[email protected]:68:4d:28:07:70] detects radar burst on radio [11a/n/ac] and channel [104] goes into non-occupancy period. 
Oct 19 08:31:31 EFGZD01 syslog: eventd_to_syslog():AP[[email protected]:68:4d:28:07:70] detects radar burst on radio [11a/n/ac] and channel [100] goes into non-occupancy period. 

APs consider other APs as interference sources? Should this situation at all occur? Note that this is concerning the 5 GHz band only.

/ Johan Axelsson

Same issue here. Really annoying as we only have 4 non DFS channels.