Moodlebox 4.0.0 : Wifi connections drops after each request

Hannes

Hello

The new features of Moodlebox 4.0.0 look very promising, so I downloaded Moodlebox 4.0.0 this week and installed it on a RPi 3B (32GB SD card).

The issue is that the Wifi signal is unstable.

I can connect to http://moodlebox.home/ but after each request the Wifi signal drops to 0%.
After about a minute it comes back and I can issue the next request.
The power supply was part of the RPi kit, the red light is steady .
a ping (see below) illustrates the problem
I can also do a ssh connection but even during the connection the Wifi signal drops and it is difficult to type commands as the signal goes off.

What should I try to resolve this issue? Any suggestions for further analysis?
As client I used two Linux PCs one with an Ubuntu 20.04 derivative, the other with a six years old Linux Mint a tablet and a mobile phone. The screen on the mobile phone is to small to do administrative tasks so I could not test it properly. The hardware is rather old.

Regards

Hannes

ping 10.0.0.1
PING 10.0.0.1 (10.0.0.1) 56(84) bytes of data.
64 bytes from 10.0.0.1: icmp_seq=1 ttl=64 time=1.99 ms
64 bytes from 10.0.0.1: icmp_seq=2 ttl=64 time=3.30 ms
From 10.0.0.145 icmp_seq=3 Destination Host Unreachable
From 10.0.0.145 icmp_seq=4 Destination Host Unreachable
From 10.0.0.145 icmp_seq=5 Destination Host Unreachable
From 10.0.0.145 icmp_seq=6 Destination Host Unreachable
From 10.0.0.145 icmp_seq=7 Destination Host Unreachable
From 10.0.0.145 icmp_seq=8 Destination Host Unreachable
64 bytes from 10.0.0.1: icmp_seq=9 ttl=64 time=1054 ms
64 bytes from 10.0.0.1: icmp_seq=10 ttl=64 time=17.6 ms
64 bytes from 10.0.0.1: icmp_seq=11 ttl=64 time=3.06 ms
From 10.0.0.145 icmp_seq=12 Destination Host Unreachable
From 10.0.0.145 icmp_seq=13 Destination Host Unreachable
From 10.0.0.145 icmp_seq=14 Destination Host Unreachable
^C
--- 10.0.0.1 ping statistics ---
17 packets transmitted, 5 received, +9 errors, 70.5882% packet loss, time 16311ms
rtt min/avg/max/mdev = 1.987/216.025/1054.222/419.137 ms, pipe 4

=============================================================

ssh moodlebox@10.0.0.1
The authenticity of host '10.0.0.1 (10.0.0.1)' can't be established.
ECDSA key fingerprint is SHA256:r4ptrYLx6phIkR19knnZTLk64W2F3jsRkQ/oBMdBnw4.
Are you sure you want to continue connecting (yes/no/[fingerprint])? yes
Warning: Permanently added '10.0.0.1' (ECDSA) to the list of known hosts.
moodlebox@10.0.0.1's password: 
Linux moodlebox 5.10.63-v7+ #1459 SMP Wed Oct 6 16:41:10 BST 2021 armv7l

<...raspberry pi picture here>

This is MoodleBox version 4.0.0, 2021-11-09.

MoodleBox is made by Nicolas Martignoni, https://github.com/martignoni/.
Please read the documentation at https://moodlebox.net/.

Last login: Wed Nov 10 06:41:19 2021 from 10.0.0.14
moodlebox@moodlebox:~ $

Edit: Code formatting.

Nicolas

Hannes This could be a bug with the new minimal firmware. See also this.

krause

Hi Hannes,
do you have another wifi on the same wifi channel?
The MoodleBox uses the following settings by default.

SSID MoodleBox
Password moodlebox
Country CH
Channel 11

Kind regards, Ralf

krause

There are three MoodleBox wifi on three different channels. The strongest wifi is Bertha. It uses a 40MHz signal.

The screenshot is made with the open source „wifi analyser“. You can get ist from F-Droid. For mor Information please look at https://vremsoftwaredevelopment.github.io/WiFiAnalyzer/

Hannes

Hello Krause
Thank you for the recommendation to use WifiAnalyzer on a mobile phone to check if there are channels used by other access points. So not far as I can see. However I do not know what 5(3) means. And there is only one Moodlebox wifi meanwhile you had three.

Maybe I should change the MoodleBox default SSID settings from country CH to GH where I use it and maintain the channel?

SSID MoodleBox
Password moodlebox
Country CH
Channel 11

If yes in which file is that done?

Kind regards
Hannes

Nicolas

Hannes If yes in which file is that done?

Please use the GUI to do this: https://moodlebox.net/en/help/updating-wi-fi-network-configuration/#change-wi-fi-regulatory-country-of-the-access-point-from-version-250

krause

Your channel graph looks fine. I think that 5(3) means channel 5 and width 3. My Bertha wifi is on channel 1 and has also the with 3. In your wifi analyser you were connected to the MoodleBox wifi. The graph shows a wider line for the MoodleBox wifi.

Now you can analyse the time graph. Connect the wifi analyser with the MoodleBox wifi. The time graph for the MoodleBox will be the wider line again. Now you can check the stability of the MoodleBox wifi. If the line breaks and the wifi analyser disconnects then you will have a problem. I tested this for over 4 hours and I got no break with the MoodleBox 4.0.0 image. I tested this with a Raspberry Pi 4B, a Raspberry Pi 3B+ and a Raspberry Pi 3B at the same time. I needed to rename the wifi ssid for the MoodleBoxes.

Ralf

krause

The country code allows and disallows some wifi channels. https://en.wikipedia.org/wiki/List_of_WLAN_channels#2.4_GHz_(802.11b/g/n/ax)

The MoodleBox uses the wifi standard 802.11n. If you choose the wifi country US then the RaspiOS should not allow the channels 12 and 13. In most other countries these channels 12 and 13 are allowed. The next two pictures show the none overlapping channels for 802.11g. As you see you should only use the channels 1, 5, 9, and 13 because these channels do not overlap. For my teachers workshops I want to get more ... so I'm using 1, 4, 7, 10, and 13 without any problem.

Ralf

Hannes

Hi again

Thank you for the help. The results so far:

The wifi access point time graph analysis with the WifiAnalyzer app on the phone connected to the MoodleBox Wifi shows no dropping of the signal. The resolution seems to be too low because a concurrent ping 10.0.0.1 test continues to show the dropping of the signal.
!
With the other Wifi net (=the local router) switched off the dropping of the signal continues:
I used the Moodle box web gui to change the Wifi settings:
From country 'Switzerland' to 'Ghana' while maintaining channel 11.

The result is similar. I also tested the access with another tablet and could do some work on it. But the response time was rather slow. Because of the dropping of the wifi signal and the re-connection time used I guess.
To check against another system I used another micro sd card with
https://www.raspberrypi.com/software/operating-systems/
Raspberry Pi OS Lite --- Release date: October 30th 2021 installed.
I connected through the local wifi run the ping command
ping 192.168.1.11
.....
64 bytes from 192.168.1.11: icmp_seq=562 ttl=64 time=3.26 ms
64 bytes from 192.168.1.11: icmp_seq=563 ttl=64 time=7.14 ms
64 bytes from 192.168.1.11: icmp_seq=564 ttl=64 time=3.26 ms

--- 192.168.1.11 ping statistics ---
564 packets transmitted, 545 received, 3.36879% packet loss, time 564188ms
rtt min/avg/max/mdev = 2.402/7.476/1213.642/52.849 ms, pipe 2

The results so far seem to indicate that it is not an access point channel conflict and probably also not a hardware problem of the Pi3B+ though I am not sure if the test in under point 4 covers the access point issue properly.

What should I try next?

Regards
Hannes

Hannes

P.S. Point 4 tests the RPi as a Wifi client, not as an access point, I suppose.

Hannes

Hi again

Update: I installed a moodlebox-3.12.0.img on a different micro sd card.
There is no problem with the wifi signal as the following ping test shows.

Moodlebox
Version 3.12.0, 2021-07-11.

ping 10.0.0.1
.........
64 bytes from 10.0.0.1: icmp_seq=499 ttl=64 time=3.52 ms
64 bytes from 10.0.0.1: icmp_seq=500 ttl=64 time=3.09 ms
64 bytes from 10.0.0.1: icmp_seq=501 ttl=64 time=4.48 ms
64 bytes from 10.0.0.1: icmp_seq=502 ttl=64 time=16.1 ms
64 bytes from 10.0.0.1: icmp_seq=503 ttl=64 time=2.50 ms
^C
--- 10.0.0.1 ping statistics ---
503 packets transmitted, 503 received, 0% packet loss, time 502796ms
rtt min/avg/max/mdev = 1.398/7.450/323.424/24.228 ms

So I plan to work with version 3.12.0.
I am though ready to do inquiries why version 4.0.0 has problems if somebody can show me how to enable debugging / tracing of the access point activities.

But as for moodlebox version 3.12.0
I do not know the moodle admin account user name and password for 3.12.0. I did not find it on the moodlebox.net website. Could somebody help me please?

--Hannes

Hannes

The admin user name / password for Moodlebox 3.12.0 is also
moodlebox
MoodleBox4$

Nicolas

Indeed. This has not changed since MoodleBox 2.6.0. See: https://moodlebox.net/en/help/moodlebox-credentials/.

Hannes

I understand that Moodlebox 4.1.0 will have a different firmware software for the wireless access point (AP). And that your tests went well so far. Is the test image available for download?

Nicolas

Hannes I understand that Moodlebox 4.1.0 will have a different firmware software for the wireless access point (AP).

It depends. MoodleBox relies on the official Raspberry Pi OS. The new minimal firmware is already included in MoodleBox 4.0.0, and the tests went well indeed. ~~I'm afraid I got no other feedback of buggy behaviour than this.~~

For next version, there's no plan to use unofficial firmware, but if Raspberry Foundation updates the firmware, we'll have a new one.

And there's no test image yet. For reference, progress towards next version can be followed in Github.

Edit: There's another similar feedback (in french), but with no detail.

Hannes

So the firmware for the AP currently included in Moodlebox 4.0.0 is a minimal one and from the official RPi OS distribution. It is supposed to support more WIFI clients again.

So for my case I continue to use Moodlebox 3.12.0 (which needs an ethernet cable to connect to another network) and check for news from time to time.

krause

There another report about this problem
https://github.com/iiab/iiab/issues/2853#issuecomment-1004439533

Nicolas

krause I think this is not the same issue: the wireless chip firmware version is different. On MoodleBox 4.0.0, version is 7.45.241. The report linked shows older version 7.45.18.

FYI: Check your wireless chip firmware version with

dmesg | grep brcmfmac

You'll get a line like

[    6.328844] brcmfmac: brcmf_c_preinit_dcmds: Firmware: BCM4345/6 wl0: Nov  1 2021 00:37:12 version 7.45.241 (1a2f2fa CY) FWID 01-5209c09

indicating the version.

moodlemuse

Hello, any updates on this topic? Is anyone else using Moodle 4 yet and can report on the stability of wifi connections.

Ratna

moodlemuse Right now I don't have a RPi 4. When I tested about two years ago http://www.syndrega.ch/blog/#benchmarking-moodlebox-on-different-raspberry-pi-models, Pi 4 wireless performance/stability was not different from either 3 B or 3 B+. I don't expect the situation to be different today, because they still share same the wireless circuitry and firmware. Insufficient power supplies and conflicting wireless transmitters (sending on the same channel) have been the main causes of instability as reported here.