Unable to connect to OctoPrint web interface

What is the problem?
I am unable to connect to OctoPrint that I installed on my Raspberry Pi. I installed it by the Raspberry Pi Imager program to an SD card and put it into my Pi. I can access the Pi through SSH but I cannot connect to the web interface. If I try connecting to the web interface quickly I can see that "OctoPrint is still starting up" and then it'll complete and reload the page, but all I get is:

This page isn’t working right now
[ip address] didn’t send any data.

ERR_EMPTY_RESPONSE

What did you already try to solve it?
I have tried reloading the image, downloading an image from GitHub, tried an older image (same result), kept everything stock (I'm using a Linksys Wireless-G USB adapter that I had to install firmware for, still couldn't connect even before installing the adapter), and tried it on a different LAN network without the WiFi adapter. I have not tried a direct connection to my PC because that is more trouble configuring a LAN connection than I'm ready to take.

Logs (syslog, dmesg, ... no logs, no support)

dmesg

octopi dmesg - Pastebin.com

octoprint.log

octoprint.log - Pastebin.com

System Info
I am unable to retrieve this. Whenever I run the octoprint systeminfo command the system hangs and then a new prompt pops up. No files are printed to the terminal or written even if I try redirecting the output to a file. As I do not have web interface access I cannot download the bundle either.

Haproxy.log

pi@octopi:~/oprint/bin $ cat /var/log/haproxy.log
Dec 2 07:00:10 octopi haproxy[776]: Proxy public started.
Dec 2 07:00:11 octopi haproxy[776]: Proxy octoprint started.
Dec 2 07:00:11 octopi haproxy[776]: Proxy webcam started.
Dec 2 07:00:11 octopi haproxy[776]: Proxy webcam_hls started.
Aug 14 18:28:42 octopi haproxy[776]: [WARNING] 336/070010 (776) : Exiting Master process...
Aug 14 18:28:42 octopi haproxy[776]: [ALERT] 336/070010 (776) : Current worker 784 exited with code 143
Aug 14 18:28:42 octopi haproxy[776]: [WARNING] 336/070010 (776) : All workers exited. Exiting... (143)
Aug 14 18:29:41 octopi haproxy[490]: Proxy public started.
Aug 14 18:29:41 octopi haproxy[490]: Proxy octoprint started.
Aug 14 18:29:41 octopi haproxy[490]: Proxy webcam started.
Aug 14 18:29:41 octopi haproxy[490]: Proxy webcam_hls started.

syslog

syslog - Pastebin.com

Additional information about your network
It is a Raspberry Pi 3 model B. I'm using a Linksys Wireless-G USB adapter (the really old kind), and I'm trying to use it on an Ender 3 printer. My router I am configuring the Pi and connecting to it through a TP-Link C50 router and it's running as an extension to my main router. I also tested this on a factory reset Edimax router so I'm fairly certain I can rule out my jank network setup.

Any help is greatly appreciated.

sounds to me like the pi crashes
You can check how long the pi is running with uptime in ssh.

Btw you need to enter ~/oprint/bin/octoprint systeminfo . for the full dump. The . makes the difference :slight_smile:

Are you sure the power supply is sufficient? Did the red led on the pi blink or turn off?
If the printer was already connected to the pi try to disconnect it.

Did you try it with another sd card? (just to rule out a bad card)

May I ask why? The pi 3 got integrated 2.4 GHz wifi.

Btw you need to enter ~/oprint/bin/octoprint systeminfo . for the full dump. The . makes the difference :slight_smile:

Tried that too. Didn't make a difference. No, I don't believe the Pi is crashing, I would have seen something happen on the monitor I had it connected to (I decided to plug it in to a monitor just to see when it finished booting). When I type the command the prompt just sits there as if it's working but then nothing is printed and a new prompt pops up. Unless Linux manages to crash and recover silently I don't believe that is what's happening.

Are you sure the power supply is sufficient? Did the red led on the pi blink or turn off?
If the printer was already connected to the pi try to disconnect it.

I'm fairly certain it's a good power supply. Got it off Amazon in a kit.

It does this whenever or not I have the printer connected, USB webcam, or the USB WiFi adapter plugged in and instead wired to LAN. I can SSH into the Pi by either interface, WiFi or LAN, and the Pi reports those addresses can be used, but I can't access the web interface.

May I ask why? The pi 3 got integrated 2.4 GHz wifi.

Maybe it's not a version 3? I thought it looks like one but it might be a version 1 model B. Could that be why I'm having issues?
To answer the question besides that, because I had it laying around, my network is Wireless-N so reverse capable with G, it supports WPA security, and because it's cute. Also, I'm proud I managed to get it to work on the Pi. It made me happy setting it up. Please don't take that away from me :frowning:

Thank you for replying. Anything else I need to provide?

It is indeed not a Raspberry Pi 3 model B. The logs show the following:

Raspberry Pi Model B Plus Rev 1.2

Though OctoPrint 'should' work on the Pi '1' model B+, the minimum recommended configuration is a Pi 3 model B.

So, is that why I'm having issues? Do I need to get myself a newer Pi? Should I just install OctoPrint to my laptop instead? Maybe I'll just get an old Dell desktop with WinXP specs and run it headless, sit the printer on top of it. That should work I'm hoping, even have enough power if I didn't want to run it headless

No that shouldn't be the cause of your problems - but I can tell you that a first gen pi is really slow.
Startup, installing stuff and just connecting to the webinterface takes a long time and your printer might stutter sometimes when the cpu is overloaded.

If you can get another device like this old laptop, I would really recommend using that instead.
A mini pc or nuc would also work fine. Sometimes you get really good deals on ebay.

Ok back to your problem. Since it's a non overclocked stock pi 1 startup can take a while.
I would flash a fresh image (just to to make sure previous restarts didn't brake anything) and let the pi boot for a while.

Tested it on a stock pi1 a few minutes ago and it took about 8+ minutes until I was able to reach the webinterface.
Depending on the used sd card it could take even longer on your pi.

Also try it on lan first if possible. If that works you can still use your wifi dongle :slight_smile:

I can see it takes a while to start up. I can access the web interface when it's starting up and it tells me it's doing so and to wait. If I leave my web browser on that page it will eventually update and say "OctoPrint is ready, refreshing the page". After that however, I get the ERR_EMPTY_RESPONSE code from before.

I have done this. I've let it sit after a clean image on LAN for a whole workday and gone back to it. Still couldn't access the web interface.

I don't believe the SD card is at fault. If that was the case, I'm not sure I'd be able to do anything on the Pi via SSH.

I have tried it on LAN before ever installing the WiFi NIC. Still get the same result.

I believe I'm just going to try a Dell desktop for now. This doesn't seem like a common issue people have so trying a different machine might be the next thing to try. If it still doesn't work then either my network hates OctoPrint or I'm cursed. Guess if I have any other problems from here on I'll post again. Also keep an ear out just in case someone else suggests something. Thank you all

1 Like

I believe I've come across the issue, however I'm not completely sure that's the case. Mainly, I've heard that the Pi 1 has networking issues, maybe even permission issues, but that could be what was causing me to not be able to connect to the web interface.
Either way, I've decided to try installing OctoPrint on Slackware using an older Dell Optiplex 755 (a whole dual-core, 6GB of RAM, and a 250GB SSD wooo!). That had its hurdles and I still need to get the webcam to play, but it worked! Maybe consider making a tutorial on my experience.
In the end, I borrowed a Pi 3 model B from a friend and put my OctoPi SD card into it and got a working system. Got a sleeve printed for the Pi, I'm good now. Thanks for everyone who posted on here. I may have not got a solution to my problem, but I got it resolved in the end.

1 Like