show acsp neighbor returns nothing in 5ghz band

[tobias_protz]

When sending the command "show acsp neighbor" to our AP250 access points, some return absolutely nothing in the 5ghz band, i.e. on their wifi1 interface - even though the interface is up and running on a completely normal frequency band, unhindered by anything nearby.

At least SOME clients or the nearest access point should show up I assume?

Does anyone have any idea how this can happen?

[samantha_lynn]

Ashley has a good point about DFS channels, and I would just like to add on to that, you may have clients in power save mode on your network which would prevent those scans with your current settings. I'd recommend enabling background scans when clients are in power save mode within your Radio profile, and to make sure you aren't on a DFS channel.

[ashley_finch]

Is the AP on a DFS(UNII-2 Extended) channel?

[tobias_protz]

Thanks sam, I get the following result on the affected APs:

BGSCAN allow=enabled; BGSCAN during voice=disabled; BGSCAN interval=10 minutes;

BGSCAN with client=enabled; BGSCAN with PS client=disabled;

Number of BGSCAN=0; Number of BGSCAN requested=0; Number of BGSCAN missed=0;

Seems they do not scan at all on that interface, correct? The AP has been up for 17 days since the last reset, I would assume that it would've performed some scans during that time.

[samantha_lynn]

That likely means we aren't getting background scans through on that interface. If you run the command "show int wifi1" and look for BGSCANs, you should be able to see how many scans have been requested, successful, and missed for that interface.

You can adjust the background scan settings in the Radio profile to allow or block scans when you have clients connected, when you have clients in a power save move, and/or when you have voice traffic on the VLAN. I'd recommend enabling background scans for when you have clients connect and clients in power save move, and leave them disabled when there is voice traffic to avoid interrupting the VOIP packets.