Server crashed after adding ArcWelder plugin

[DaveJJ]

What is the problem?

The Octopi server no longer runs after trying to add ArcWelder plugin. When trying to login I am greeted with " The OctoPrint server is currently not running"

What did you already try to solve it?

I tried the advice given on the page with the above greeting and eventually ssh'd into the Pi and looked at the logs, most of which means nothing to me. However an error is reported in connection with the ArcWelder plugin which makes me suspect that it is not compatible.

Have you tried running in safe mode?

Yes, by running,

sudo service octoprint stop
sudo ~/oprint/bin/octoprint serve --safe

which showed a lot of text ending with

ValueError: bad marshal data (string ref out of range)

Did running in safe mode solve the problem?

Safe mode did not start.

Complete Logs

octoprint.log, serial.log or output on terminal tab at a minimum, browser error console if UI issue ... no logs, no support! Not log excerpts, complete logs.)

######## Octoprint.log ############

2021-03-02 17:19:12,799 - octoprint.plugin.core - ERROR - Error loading plugin logging
Traceback (most recent call last):
  File "/home/pi/oprint/local/lib/python2.7/site-packages/octoprint/plugin/core.py", line 1298, in _import_plugin
    module = _load_module(module_name, spec)
  File "/home/pi/oprint/local/lib/python2.7/site-packages/octoprint/plugin/core.py", line 69, in _load_module
    return imp.load_module(name, f, filename, details)
  File "/home/pi/oprint/lib/python2.7/site-packages/octoprint/plugins/logging/__init__.py", line 19, in <module>
    from octoprint.server import NO_CONTENT
  File "/home/pi/oprint/local/lib/python2.7/site-packages/octoprint/server/__init__.py", line 48, in <module>
    from octoprint.server import util
  File "/home/pi/oprint/local/lib/python2.7/site-packages/octoprint/server/util/__init__.py", line 24, in <module>
    from . import flask, sockjs, tornado, watchdog  # noqa: F401
  File "/home/pi/oprint/local/lib/python2.7/site-packages/octoprint/server/util/flask.py", line 23, in <module>
    import tornado.web
  File "/home/pi/oprint/local/lib/python2.7/site-packages/tornado/web.py", line 95, in <module>
    from tornado.routing import (AnyMatches, DefaultHostMatches, HostMatches,
  File "/home/pi/oprint/local/lib/python2.7/site-packages/tornado/routing.py", line 184, in <module>
    from tornado.httpserver import _CallableAdapter
  File "/home/pi/oprint/local/lib/python2.7/site-packages/tornado/httpserver.py", line 33, in <module>
    from tornado.http1connection import HTTP1ServerConnection, HTTP1ConnectionParameters
ValueError: bad marshal data (string ref out of range)
2021-03-02 17:19:13,255 - octoprint.startup - INFO - Added settings overlay from plugin firmware_check
2021-03-02 17:19:13,258 - octoprint.plugin.core - INFO - Found 14 plugin(s) providing 10 mixin implementations, 17 hook handlers
2021-03-02 17:19:13,374 - octoprint.cli.server - ERROR - Uncaught exception
Traceback (most recent call last):
  File "/home/pi/oprint/bin/octoprint", line 8, in <module>
    sys.exit(main())
  File "/home/pi/oprint/local/lib/python2.7/site-packages/octoprint/__init__.py", line 939, in main
    octo(args=args, prog_name="octoprint", auto_envvar_prefix="OCTOPRINT")
  File "/home/pi/oprint/local/lib/python2.7/site-packages/click/core.py", line 829, in __call__
    return self.main(*args, **kwargs)
  File "/home/pi/oprint/local/lib/python2.7/site-packages/click/core.py", line 782, in main
    rv = self.invoke(ctx)
  File "/home/pi/oprint/local/lib/python2.7/site-packages/click/core.py", line 1259, in invoke
    return _process_result(sub_ctx.command.invoke(sub_ctx))
  File "/home/pi/oprint/local/lib/python2.7/site-packages/click/core.py", line 1066, in invoke
    return ctx.invoke(self.callback, **ctx.params)
  File "/home/pi/oprint/local/lib/python2.7/site-packages/click/core.py", line 610, in invoke
    return callback(*args, **kwargs)
  File "/home/pi/oprint/local/lib/python2.7/site-packages/click/decorators.py", line 21, in new_func
    return f(get_current_context(), *args, **kwargs)
  File "/home/pi/oprint/local/lib/python2.7/site-packages/octoprint/cli/server.py", line 315, in serve_command
    ignore_blacklist,
  File "/home/pi/oprint/local/lib/python2.7/site-packages/octoprint/cli/server.py", line 144, in run_server
    from octoprint.server import Server
  File "/home/pi/oprint/local/lib/python2.7/site-packages/octoprint/server/__init__.py", line 48, in <module>
    from octoprint.server import util
  File "/home/pi/oprint/local/lib/python2.7/site-packages/octoprint/server/util/__init__.py", line 24, in <module>
    from . import flask, sockjs, tornado, watchdog  # noqa: F401
  File "/home/pi/oprint/local/lib/python2.7/site-packages/octoprint/server/util/flask.py", line 23, in <module>
    import tornado.web
  File "/home/pi/oprint/local/lib/python2.7/site-packages/tornado/web.py", line 95, in <module>
    from tornado.routing import (AnyMatches, DefaultHostMatches, HostMatches,
  File "/home/pi/oprint/local/lib/python2.7/site-packages/tornado/routing.py", line 184, in <module>
    from tornado.httpserver import _CallableAdapter
  File "/home/pi/oprint/local/lib/python2.7/site-packages/tornado/httpserver.py", line 33, in <module>
    from tornado.http1connection import HTTP1ServerConnection, HTTP1ConnectionParameters
ValueError: bad marshal data (string ref out of range)

########### serial.log ##########

2021-01-30 17:39:50,155 - serial.log is currently not enabled, you can enable it via Settings > Serial Connection > Log communication to serial.log

Additional information about your setup

OctoPrint version, OctoPi version, printer, firmware, browser, operating system, ... as much data as possible

octoprint 1.5.3
Don't Know
CTC Prusa I3 pro B (clone)
firmware 1.8.0 (I think)
Firefox 86.0 (64bit)
Ubuntu 20.04

[seb]

If not mistaken logging plugin is causing issues. I've understood that logging is now standard python functionality.
try
pip uninstall logging

[DaveJJ]

Thanks for the prompt reply.
Tried your advice but was greeted with

sudo pip: command not found

Used

sudo apt install pip
sudo pip uninstall logging

received

Skipping logging as it is not installed.

What version pip and python should I be using as it is all very confusing with all the versions and module names?
Thanks again for your reply.

[foosel]

On OctoPi: ~/oprint/bin/pip

Unless you want to restart OctoPrint or the webcam server, you never need sudo on OctoPi.

[DaveJJ]

@foosel

Thanks, interesting fact. used to using root or sudo for most occasions with linux.

[foosel]

sudo means, running something with super user rights. That will make everything work that somehow can, but doesn't mean you should be running as superuser, and in fact it can also break stuff (by setting the wrong permissions on newly generated files for example) so that now the way something was meant to work also no longer works unless you run it with sudo. Throwing sudo at every single problem encountered while working with Linux is a bad idea, understanding why something is throwing an error and how that could be fixed with a minimal set of additional permissions is the better and also safer approach.

[DaveJJ]

@foosel
Thanks for the heads up! Unfortunately I have not tracked down the solution to my broken system. As pip did not initially work because it was not installed I looked at the possibility that the python might need to be upgraded to v3 as hinted in the octoprint bulletins. I have cloned the SD card to preserved the system state as I didn't think I would be able to do a backup easily from CLI and tried to run the script offered here

Upgrade your OctoPrint install to Python 3!

Since OctoPrint version 1.4.0, the codebase has supported installation on both Python 2 and Python 3 environments, as a result of Python 2’s EOL status. However, at the time of writing, only 2.3% of all tracked installs are running on Python 3. The main reason for this is that all current OctoPi releases up until now shipped with OctoPrint installed under Python 2. But there was also the issue of compatibility of the plugins in the plugin repository - there’s no point installing…

but ran into more problems with error messages

Detecting system info...
OctoPi version: 0.17.0
Getting OctoPrint version...
OctoPrint version: 1.5.3
Reading installed plugins...
No handlers could be found for logger "octoprint.plugin.core"
Usage: octoprint plugins [OPTIONS] COMMAND [ARGS]...
Try 'octoprint plugins --help' for help.

Error: No such command 'backup:backup'.
ERROR: Failed to create OctoPrint backup
Fatal error, exiting

It's beginning to look like I may have seriously broken the system and a reinstall could be the easier route, can anyone suggest anything further?