Duet Wifi Webserver not responding

dc42

Thanks, I'll ask chrishamm to take a look (he wrote DWC and is German himself).

The "oem.json not found" is normal, that's an optional file.

The "could not load the script" is odd. Are any further details given about the nature of that error?

Nuvag

No, got no further details. But it noticed sometimes it takes >30 seconds to load http://192.168.178.15/js/dwc.js in an own browser tab, so i suspect its a timeout. After restarting wifi the loadtime is consistantly around 1 second.
This javascript is very large, above 1MB (300 KB zipped) and not cached in the browser. This could probably be optimized, but should not be the root cause. But if memory is in short supply and the gzip version is created on the fly this could be a problem(?)

webinterface just lost connection again, this time if found an "Unexpected state change on socket X":

New conn on socket 6 for local port 80
Found responder
Received 488 bytes
New conn on socket 7 for local port 80
Found responder
Received 475 bytes
Client disconnected on socket 6
New conn on socket 6 for local port 80
Found responder
Received 475 bytes
New conn on socket 7 for local port 80
Found responder
Received 488 bytes
New conn on socket 6 for local port 80
Found responder
Received 475 bytes
Unexpected state change on socket 7
New conn on socket 7 for local port 80
Found responder
Received 488 bytes
New conn on socket 6 for local port 80
Found responder
Received 475 bytes
Unexpected state change on socket 7
New conn on socket 7 for local port 80
Found responder
Received 488 bytes
New conn on socket 6 for local port 80
Found responder
Received 488 bytes
Unexpected state change on socket 7

dc42

What make and model is your router?

parovoZZ

Hi!

Same problem. Try connect … connect ... connect ... F5 ... nothing.

I connect via USB. I make Disable Wi-Fi / Enable Wi-Fi. After that it works 1 hour ... 2 ... 3 hours ... Ping is always stable (2-100 ms).

1.20 firmware.

Nuvag

I'm using a Fritz!Box 7490.

Just now lost connection again (webinterface won't load at all, but ping is successful) and tried your instruction but with no usefull output during deactivating/activating http and couldn't connect after that.

>>> M552
SENDING:M552
WiFi module is connected to access point ewl-internet.ch_40357, IP address 192.168.178.15
>>> M586 P0 S0
SENDING:M586 P0 S0
HTTP is disabled
>>> M586 P0 S1
SENDING:M586 P0 S1
HTTP is enabled on port 80

I tried rebooting the Fritz!Box and duet wifi will timeout while trying to reconnect (as booting the router takes about a minute). I reactivated wifi with M552 S1 but webinterface will still not load. Diable/Enable HTTP did again not help. (ping does work)
Disabling and reenabling Wifi (M552 S0 M552 S1) did bring the webinterface back.
So M552 S0 seems to "unblock" the webinterface.

Did not yet update the webserver to 1.21, will do next.

Nuvag

Tonight i printed a model and closed the webinterface windwo in the brower.
This morning i couldn't connect to the webinterface (but ping still ok), so its probably not the polling from the webinterface thats causing the issue.
The log only contains about a hundret entries "Class Network spinning", no error messages.

dc42

When you are unable to connect but able to ping, if you run M552 without parameters, does it report that the Duet is connected to your network, or not?

Nuvag

Yes, i actually included that part in my last message because i thought you would ask that

>>> M552
SENDING:M552
WiFi module is connected to access point ewl-internet.ch_40357, IP address 192.168.178.15

Nuvag

Updated Webserver to 1.21.RC1 and immediatly having an instable connection, debug log:

WiFi: fGLUE: fragmented pbuf (932!=1514)!
WiFi: GLUE: fragmented pbuf (932!=1514)!
WiFi: GLUE: fragmented pbuf (932!=1514)!
WiFi: GLUE: fragmented pbuf (932!=1514)!
[...]

When reloading the page:

Unexpected state change on socket 0
Can't send anymore
New conn on socket 0 for local port 80
HTTP connection accepted
Found responder
New conn on socket 5 for local port 80
HTTP connection accepted
Found responder
Received 330 bytes
Sending reply, file = yes
HTTP req, command words { GET / HTTP/1.1 }, parameters { }
Received 339 bytes
Sending reply, file = yes
HTTP req, command words { GET /css/dwc.css HTTP/1.1 }, parameters { }
New conn on socket 0 for local port 80
HTTP connection accepted
Found responder
Received 357 bytes
Sending reply, file = yes
HTTP req, command words { GET /js/dwc.js HTTP/1.1 }, parameters { }
WiFi: GLUE: fragmented pbuf (788!=1514)!
[...]

Still having the same issue with http://192.168.178.15/js/dwc.js

When the connection is stable there are no messages with 'WiFi: GLUE: fragmented pbuf <…>', so this might be the cause of the problem.

Edit:
Additionally there is a problem with the html in line 1708:

should be

Nuvag

Webinterface was online 6 hours without a problem then failed again.
I used Wireshark to capture the network traffic, maybe this can help fpr further analysis.

This happened in the moment the connection was lost:
https://www.dropbox.com/sh/r9zkw9id482i9z0/AAA-x0NTtIISPxijZnqTiZj0a/Wireshark_DuetWifi.PNG?dl=0
This was from Microsoft Edge Browser. So my PC sent an reset and from then on all requests to the duet wifi return a reset. This continues until the ajax retry limit is reached (i set it to 50 retries).
I found other occurences earlier where my PC closed the connection but a new one could be established without problems.

Then tried to open the webinterface in a different browser (Firefox) and got:
https://www.dropbox.com/sh/r9zkw9id482i9z0/AADPnonPL1ApvNZzF8qBnV-Va/Wireshark_DuetWifi_2.PNG?dl=0

I suspect for some reason all available sockets from the wifi module in the duet to the internal modules get blocked and won't be unblocked until restarting the wifi. This would explain why the wifi connection works in general (can ping and open tcp connection) but it fails when trying to get the status report.

dc42

Thanks, I suspected that these problems might be caused by a lack of sockets. Which version of DuetWiFiServer are you using?

Nuvag

Firmware Name:
RepRapFirmware for Duet WiFi
Firmware Electronics:
Duet WiFi 1.0
Firmware Version:
1.20 (2017-12-23)
WiFi Server Version:
1.21RC1
Web Interface Version:
1.20

parovoZZ

Hi!

Is it possible to make a program reset of the Wi-Fi module on an external button? For example, execute a script:

M552 S-1;

M552 S1;

?

dc42

Yes, if you set up a trigger using M581.

T3P3Tony

if you do that I think you will need a pause in between the M552 S-1 and M552 S1 commands (I tried to make a macro for this but the S1 was executed too soon after the disable (while the wifi was still changing state) so it did not work.

parovoZZ

And then what to do?
Now I connect a USB cable during printing…...brrrrrr))))

dc42

You can insert a pause between the two M552 commands using G4.

parovoZZ

G4 is bad. Stops printing ….
Is there a NOP command?

dc42

Good point, if a print is running then G4 will wait for everything to stop. Try this:

M552 S0 ; disconnect and shutdown wifi services
M587 ; list access points, with luck this will wait for the shutdown to complete
M552 S-1
M552 S1

Danal

Another data point:

I lost connection to a DuetWifi during a long print. About six hours in. M582 (via PanelDue) stop/start did not fix. M552 stop/start and connectivity was fine.

Firmware Name: RepRapFirmware for Duet WiFi
Firmware Electronics: Duet WiFi 1.0
Firmware Version: 1.20 (2017-12-23)
WiFi Server Version: 1.20
Web Interface Version: 1.20

Wireless router is a Google WiFi mesh. It is about 15 feet from the printer. It is also true that my Desktop PC is cabled to that same Google node that serves the printer, and the wireless mesh from that node is the only connectivity available to my PC. Meaning that I'd know it instantly if the router mesh node itself dropped.

As mentioned, just another data point. No explicit reply needed.