hAP ac lite selecting illegal frequency with scan list

RouterOS Wireless Networking
1

In order to do some further investigation on Wi-Fi 6 on my hAP ax2, I’ve just commissioned a hAP ac lite I had spare to takeover the current Wi-Fi network. Latest RouterOS v7.18.1, factory reset, security profile set-up and SSIDs renamed.

By default, frequency on 5GHz is set to auto with no scan list. However, this has the habit of selecting channels 149 and above (frequency 5745+) which is not accessible by some devices inc. my Teclast Android tablet. So I added a scan list of 5180-5720. First question, is this okay?

However, after waiting for the 10 minute DFS/CAC, the 5Ghz SSID was not visible on any device. Looking at the status, I’m not sure it’s picked a legal frequency/channel - is 5615 a legal channel for eeCe?

I’m trying to remove the scan list but this has revealed another potential bug that I’ll post separately on so currently restoring a backup.

2

No. You should enter it in Frequency property.

But I’m wondering: you’re mentioning “hAP ax” (which should be running wifi-qcom driver), but your screenshot shows “ap bridge” as AP mode (and that mode doesn’t exist in new wifi driver, it’s simply “ap”).

[edit] Ah, I see you’re talking about your old hAP ac lite.

3

One can’t enter it in the frequency property:

This is the hAP ac lite that I’m setting up to temporarily replace my hAP ax2 which I want to do some investigation on.

I’ve found the documentation and this is one area that might have changed between v6 and v7. But scan-list=5180-5720 should be accepted.

4

Use scan list values “5180-5320:20” and “5500-5700:20” and it should be OK.

5

Thanks for but doesn’t that just exclude part of the range? This post is more about a potential bug of Router OS choosing 5615/20/eeCe at all.

I’ve painstakingly gone through each 20MHz frequency from 5180-5720 and they all work. However set it manually to 5615/20/eeCe and Wi-Fi doesn’t work. I’m assuming because 5615 is not a valid control channel.

It will difficult for me to repeat this as right now, it’s picking a different channel. I’ll keep testing.

6

Can I just clarify the :20 bit in the scan list? Does 5180-5720:20 mean scan frequencies in that range in 20MHz increments? If so, then I’m guessing that without :20 the increment is not 20MHz, maybe 5MHz? That would explain why my first attempt ended up with 5615.

The documentation on this could do with a bit of an edit. The example is around setting up channel lists and not the simple case of specifying a subset of the entire frequency range.