Luci-app-statistics able to chart wifi channel?

Hi,

Is it possible to have luci-app-statistics chart the wifi channel(s) active?

It currently charts users connected, signal/noise ratio, bandwidth, etc. However I wanted to see what channel wifi hops over (it's on auto setting, so not bound to a fixed channel).

Thanks

This information is already displayed in LuCI, just not on the exact screen you noted.

Does your WiFi channel actually change often?

(Also, moving this to the Developers sections, since this is asking for a new feature in software.)

Nice! Where could I find it?

Actually I'm not sure. I live in a condo so have maybe a hundred other wifi networks in range here. I wanted to chart this to confirm.

Also my 5ghz band jumps out of the DFS band, which must be due to aircraft overhead on some days. Again, a graph would be helpful to trace this.

  • On the main overview page:
    Screenshot%20from%202018-08-08%2011-16-53

  • On the Wireless Overview Page under Network > Wireless:
    Screenshot%20from%202018-08-08%2011-20-06

  • Under the individual WiFi SSIDs under Network > Wireless:
    Screenshot%20from%202018-08-08%2011-21-19

If this is the case, choose a 5 GHz channel that doesn't use DFS, see:

Unless your router has a lot of CPU and memory, constantly running a visual graph with this information may be overkill. I'm also not sure how'd one graph a channel change, but the information is there!

Hope this helps.

I guess that's what I want to add to the RRD files, that wifi band used over time.

Something I can write my own scripts to do?

I might be wrong, but I think those status pages reflect the currently configured channel, not the one in use (in the DFS case that is).

Auto channel setting doesn’t actually mean what you think it means. It just picks the first available channel in the list from all accounts.

So picking auto-channel doesn't mean it can move around once the interface is bought up?

Does it mean it picks one at random at start time and stays there? Something else?

That is my understanding.
And I think you’ll find it always picks “1” in 2.4 and “36” in 5 because they are the first on the list.

Ok, that's helpful to know. Thanks. I should read the docs more carefully in future!

So really it's just the DFS case that I have of channels changing on me.

Would you happen to know how that picks a new channel - same rule as "auto"?

If so, I might just want a way of logging when that event happens and I can just grep for that.

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I think that is driver dependant.
Most I’ve seen jump back to 36. I think they can technically jump anywhere, but if they choose to jump back to another DFS channel they would have to scan for the mandatory wait period first of course.

If you can find a good way of monitoring that, please do share. I’ve been looking to do something similar but haven’t invested much time.

The channel displayed in these status boxes is queried directly from nl80211 and should reflect the effective setting of this moment in time.

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I'm going to see what appears in the syslog this week regarding DFS events.

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Left it running for a few days and I see this in the syslog:

Mon Aug 13 06:26:06 2018 daemon.notice hostapd: wlan1: DFS-RADAR-DETECTED freq=5500 ht_enabled=1 chan_offset=1 chan_width=2 cf1=5510 cf=0
Mon Aug 13 06:26:06 2018 daemon.notice hostapd: wlan1: DFS-NEW-CHANEL freq=5785 chan=157 sec_chan=1

So the event is logged, as is the jump - in this case to channel 157.

I've set up a nightly cron to restart the network services, which means I'm only moved for <24hrs max.

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