5Ghz 40mhz channels 120,124,128 not available

[craiglebutt]

Hi

I'm in the UK, already lead to believe we can use these channels of 5Ghz , just need to make sure the APs are fast enough to move off if detected radar which they are.

We can only use 7 of he 9 channels on 40Mhs, so want to test before going to 20Mhz on 5Ghz

Testing to see if any of our buildings are picking up radar, by moving these AP to a test WLC.

Running 8.5.182 - trying to only to make these channels available, but the APs will not connect.

Looked on prime, prime on 3.9 doesn't even show these channels available on from drop down box when customizing.

Controllers are un UK Regulatory Domain

I remember on our old WISMS kept getting radar events which had old 1240 which couldn't move off.

[Scott Fella]

On the controller, if you issue this command from the CLI, you can see what channels are in your DCA list. 

show advanced 802.11a channel

Keep in mind how DCA works, if radar is detected, the ap has to shut down the radio and look for an available channel.  Take a look at this recent post where @JPavonM described what happens when radar is detected.

Re: Static Channel Selection and DFS Validation/Query about Timer Mess - Cisco Community

[Scott Fella]

I have sites that are in the UK also and what I did is create an ap group that doesn't use DFS channels and and other group that has them.  Then I decided which AP's would be in what group so that if there is radar, the outage would be minimal.

[craiglebutt]

Thanks for reply's.

This was my first attempt before posting

On the my test wlc, only channels available are default DCA.

Allowed Channel List......................... 48,120,124,128
Unused Channel List.......................... 36,40,44,52,56,60,64,100,
104,108,112,116,132,136,140

Following recommendations for RF Group

I created the RF Profile and only allowed 120,124,128.

But the AP which is a AIR-CAP3702E-E-K9 is selecting a channel that isn't on my allowed list. 

RF Profile and AP assigned to same AP group, but the AP comes up  on (48,44)*

I've clicked on the AP to manually change the RF Channel Assignment, channels 120,124,128 are not a option to select.

Controller has the correct Country Code

[Scott Fella]

Issue show country channels this will show you the list of allowed channels for the regulatory domain you have defined. If you see the channel as allowed, then you need to go into the DCA and make sure you have those channels in the allowed list.  You can try to add the channel to the list from the cli using the following command.

config advanced 802.11a channel add <channel>

[craiglebutt]

hi

The channels are allowed as below and already in DCA cheers

Configured Country............................. GB - United Kingdom
KEY: * = Channel is legal in this country and may be configured manually.
A = Channel is the Auto-RF default in this country.
. = Channel is not legal in this country.
C = Channel has been configured for use by Auto-RF.
x = Channel is available to be configured for use by Auto-RF.
(-,-) = (indoor, outdoor) regulatory domain allowed by this country.
-----------------:+-+-+-+-+-+-+-+-+-+-+-+-+-+-
802.11bg :
Channels : 1 1 1 1 1
: 1 2 3 4 5 6 7 8 9 0 1 2 3 4
-----------------:+-+-+-+-+-+-+-+-+-+-+-+-+-+-
GB (-E ,-E A * * * * A * * * * A * * .
-----------------:+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
802.11a : 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
Channels : 3 3 3 4 4 4 4 4 5 5 6 6 0 0 0 1 1 2 2 2 3 3 4 4 4 5 5 6 6 6 7
: 4 6 8 0 2 4 6 8 2 6 0 4 0 4 8 2 6 0 4 8 2 6 0 4 9 3 7 1 5 9 3
-----------------:+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
GB (-E ,-E . A . A . A . A A A A A A A A A A A A A A A A . . . . . . . .

[Scott Fella]

Make sure you enabled Extended UNII-2 channels

[craiglebutt]

All ticked as should be.

Must be a bug some where, I'll try down grading it to a pervious version

[Scott Fella]

Must be... I was able to uncheck the Extended UNII-2 channels and all the UNII-2 channels where removed.  When I checked Extended UNII-2 channels the channels were available again to use.

[craiglebutt]

So this is from TAC, thought I'd share incase anyone in Europe has this issue.

Case summary: basically I investigate those channels in your country, I found some interesting things related to the subject. One of them was you cannot assign the Channel manually on Europe as per ETSI compliance. If the RRM is not assigning the channel, it is in use. So that’s the main reason for the issue.

[JPavonM]

Maybe this document could be of help, the only thig is that it does not cover x700 AP Series.