Initial setup "Server is offline"

What is the problem?
I am trying to setup OctoPrint for the first time and I cannot access OctoPrint via web browser because I get a "Server is offline" message. I am able to ssh into the Pi without any issues and I see it connected to my router consistently.

What did you already try to solve it?
Unplugging and plugging in the Raspberry Pi
Restarting my laptop
Re-flashing the sd card with OctoPi
Clearing my browser cache
Trying a different web browser (Firefox instead of Chrome)
Rebooting the pi via ssh command
Turning off my firewall
Resetting the timezone on the Raspberry Pi

Additional information about your setup (OctoPrint version, OctoPi version, printer, firmware, octoprint.log, serial.log or output on terminal tab, ...)
OctoPrint version: 1.3.8
OctoPi version: 0.15.1
Raspberry Pi 3B+
Printer: Ender 3
OS: Windows 10
Browser: Chrome and Firefox
Error message:

******************************************************************************
2019-01-03 12:07:44,850 - octoprint.startup - INFO - Starting OctoPrint 1.3.8
2019-01-03 12:07:44,850 - octoprint.startup - INFO - ******************************************************************************
2019-01-03 12:07:44,977 - octoprint.plugin.core - INFO - Loading plugins from /home/pi/oprint/lib/python2.7/site-packages/octoprint/plugins, /home/pi/.octoprint/plugins and installed plugin packages...
2019-01-03 12:07:47,257 - octoprint.plugin.core - INFO - Found 10 plugin(s) providing 10 mixin implementations, 4 hook handlers
2019-01-03 12:07:47,377 - octoprint.server.heartbeat - INFO - Starting server heartbeat, 900.0s interval
2019-01-03 12:07:47,414 - octoprint.server - INFO - Intermediary server started
2019-01-03 12:07:47,415 - octoprint.plugin.core - INFO - Loading plugins from /home/pi/oprint/lib/python2.7/site-packages/octoprint/plugins, /home/pi/.octoprint/plugins and installed plugin packages...
2019-01-03 12:07:47,945 - octoprint.plugin.core - INFO - Found 10 plugin(s) providing 10 mixin implementations, 4 hook handlers
2019-01-03 12:07:47,983 - octoprint.filemanager.storage - INFO - Initializing the file metadata for /home/pi/.octoprint/uploads...
2019-01-03 12:07:47,984 - octoprint.filemanager.storage - INFO - ... file metadata for /home/pi/.octoprint/uploads initialized successfully.
2019-01-03 12:07:48,017 - octoprint.plugins.softwareupdate - INFO - Loaded version cache from disk
2019-01-03 12:07:50,475 - octoprint.util.pip - INFO - Using "/home/pi/oprint/bin/python2 -m pip" as command to invoke pip
2019-01-03 12:07:52,255 - octoprint.util.pip - INFO - Version of pip is 9.0.3
2019-01-03 12:07:52,257 - octoprint.util.pip - INFO - pip installs to /home/pi/oprint/lib/python2.7/site-packages (writable -> yes), --user flag needed -> no, virtual env -> yes
2019-01-03 12:07:52,257 - octoprint.util.pip - INFO - ==> pip ok -> yes
2019-01-03 12:07:52,259 - octoprint.plugin.core - INFO - Initialized 10 plugin implementation(s)
2019-01-03 12:07:52,265 - octoprint.plugin.core - INFO - 10 plugin(s) registered with the system:
|  Announcement Plugin (bundled) = /home/pi/oprint/lib/python2.7/site-packages/octoprint/plugins/announcements
|  Core Wizard (bundled) = /home/pi/oprint/lib/python2.7/site-packages/octoprint/plugins/corewizard
|  CuraEngine (<= 15.04) (bundled) = /home/pi/oprint/lib/python2.7/site-packages/octoprint/plugins/cura
|  Discovery (bundled) = /home/pi/oprint/lib/python2.7/site-packages/octoprint/plugins/discovery
|  Logging (bundled) = /home/pi/oprint/lib/python2.7/site-packages/octoprint/plugins/logging
|  OctoPi Support Plugin (bundled) = /home/pi/oprint/lib/python2.7/site-packages/octoprint/plugins/octopi_support
|  Plugin Manager (bundled) = /home/pi/oprint/lib/python2.7/site-packages/octoprint/plugins/pluginmanager
|  Printer Safety Check (bundled) = /home/pi/oprint/lib/python2.7/site-packages/octoprint/plugins/printer_safety_check
|  Software Update (bundled) = /home/pi/oprint/lib/python2.7/site-packages/octoprint/plugins/softwareupdate
|  Virtual Printer (bundled) = /home/pi/oprint/lib/python2.7/site-packages/octoprint/plugins/virtual_printer
2019-01-03 12:07:52,284 - octoprint.environment - INFO - Detected environment is Python 2.7.13 under Linux (linux2). Details:
|  hardware:
|    cores: 4
|    freq: 1400.0
|    ram: 918192128
|  os:
|    id: linux
|    platform: linux2
|  plugins:
|    octopi_support:
|      model: unknown
|      revision: a020d3
|      version: 0.15.1
|  python:
|    pip: 9.0.3
|    version: 2.7.13
|    virtualenv: /home/pi/oprint
2019-01-03 12:07:52,293 - octoprint.server - INFO - Reset webasset folder /home/pi/.octoprint/generated/webassets...
2019-01-03 12:07:52,308 - octoprint.server - INFO - Reset webasset folder /home/pi/.octoprint/generated/.webassets-cache...
2019-01-03 12:07:52,524 - octoprint.server - INFO - Shutting down intermediary server...
2019-01-03 12:07:53,021 - octoprint.server - INFO - Intermediary server shut down
2019-01-03 12:07:53,025 - octoprint.events - INFO - Processing startup event, this is our first event
2019-01-03 12:07:53,026 - octoprint.events - INFO - Adding 0 events to queue that were held back before startup event
2019-01-03 12:07:53,028 - octoprint.filemanager - INFO - Adding backlog items from all storage types to analysis queue...
2019-01-03 12:07:53,036 - octoprint.filemanager - INFO - Added 0 items from storage type "local" to analysis queue
2019-01-03 12:07:53,066 - octoprint.plugins.discovery - INFO - Registered OctoPrint instance on octopi for _http._tcp
2019-01-03 12:07:53,089 - octoprint.plugins.discovery - INFO - Registered OctoPrint instance on octopi for _octoprint._tcp
2019-01-03 12:07:53,095 - octoprint.plugins.discovery - INFO - Registered OctoPrint instance on octopi for SSDP
2019-01-03 12:07:53,107 - octoprint.server - INFO - Listening on http://127.0.0.1:5000
2019-01-03 12:07:53,219 - octoprint.plugins.pluginmanager - INFO - Loaded plugin repository data from disk, was still valid
2019-01-03 12:07:53,710 - octoprint.plugins.pluginmanager - INFO - Loaded notice data from disk, was still valid
2019-01-03 12:07:53,713 - octoprint.server.preemptive_cache - INFO - Preemptively caching / (ui _default) for {'query_string': 'l10n=en', 'path': '/', 'base_url': 'http://192.168.0.40/'}
2019-01-03 12:08:04,437 - octoprint.server.preemptive_cache - INFO - ... done in 10.73s
2019-01-03 12:08:47,753 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 12:08:47,819 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 12:08:48,406 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 12:08:49,088 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 12:08:49,752 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 12:08:49,875 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 12:08:49,905 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 12:08:49,912 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 12:08:50,496 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 12:08:51,153 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 12:08:55,506 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 12:08:55,599 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 12:08:55,604 - tornado.application - ERROR - Exception in callback None
Traceback (most recent call last):
  File "/home/pi/oprint/local/lib/python2.7/site-packages/tornado/ioloop.py", line 836, in start
    fd_obj, handler_func = self._handlers[fd]
KeyError: 25
2019-01-03 12:08:55,621 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 12:08:55,634 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 12:08:55,641 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 12:08:55,650 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 12:08:55,659 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 12:09:02,103 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 12:09:02,185 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 12:09:02,872 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 12:09:03,700 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 12:09:04,481 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 12:09:04,591 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 12:09:04,631 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 12:09:04,658 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 12:09:05,227 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 12:09:05,879 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 12:09:10,506 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 12:09:19,215 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 12:09:19,237 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 12:09:19,305 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 12:09:21,217 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 12:09:22,261 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 12:09:22,322 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 12:09:23,218 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 12:09:28,507 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 12:09:28,532 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 12:09:34,507 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 12:09:34,534 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 12:09:34,601 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 12:09:40,506 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 12:09:40,515 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 12:22:47,379 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2019-01-03 12:24:40,535 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 12:24:40,549 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 12:24:40,560 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 12:24:40,571 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 12:24:40,581 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 12:24:40,589 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 12:24:40,602 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 12:24:40,630 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 12:24:40,658 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 12:24:40,686 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 12:24:46,507 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 12:24:46,521 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 12:24:47,222 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 12:24:47,308 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 12:24:47,348 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 12:24:49,447 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 12:24:52,505 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 12:24:52,512 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 12:25:15,048 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 12:37:47,381 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2019-01-03 12:39:41,270 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 12:39:41,333 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 12:39:42,306 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 12:39:42,371 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 12:39:42,458 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 12:39:47,506 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 12:39:47,513 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 12:45:37,482 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 12:45:37,486 - tornado.application - ERROR - Exception in callback None
Traceback (most recent call last):
  File "/home/pi/oprint/local/lib/python2.7/site-packages/tornado/ioloop.py", line 836, in start
    fd_obj, handler_func = self._handlers[fd]
KeyError: 33
2019-01-03 12:45:37,498 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 12:45:37,510 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 12:45:37,517 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 12:45:37,525 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 12:45:37,533 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 12:45:47,852 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 12:45:47,928 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 12:45:48,793 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 12:45:49,762 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 12:45:50,727 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 12:45:50,859 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 12:45:50,890 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 12:45:50,918 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 12:45:51,507 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 12:45:52,155 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 12:45:56,506 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 12:46:05,214 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 12:46:05,237 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 12:46:05,310 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 12:46:08,212 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 12:46:08,226 - octoprint.server.util.sockjs - WARNING - Could not send message to client ::ffff:192.168.0.37: object of type 'NoneType' has no len()
2019-01-03 12:46:08,232 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 12:46:08,283 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 12:46:08,351 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 12:46:09,222 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 12:46:36,246 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 12:46:41,506 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 12:46:45,228 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 12:46:45,256 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 12:47:38,296 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 12:47:38,307 - tornado.application - ERROR - Exception in callback None
Traceback (most recent call last):
  File "/home/pi/oprint/local/lib/python2.7/site-packages/tornado/ioloop.py", line 836, in start
    fd_obj, handler_func = self._handlers[fd]
KeyError: 27
2019-01-03 12:47:38,319 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 12:47:38,330 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 12:47:38,340 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 12:47:38,349 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 12:47:38,358 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 12:47:46,728 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 12:47:47,177 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 12:47:47,239 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 12:47:47,296 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 12:47:48,781 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 12:47:50,417 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 12:47:52,021 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 12:47:52,159 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 12:47:52,191 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 12:47:52,218 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 12:47:52,804 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 12:47:53,461 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 12:47:57,505 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 12:48:06,216 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 12:48:06,237 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 12:48:06,303 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 12:48:10,217 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 12:48:10,312 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 12:48:10,370 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 12:48:11,239 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 12:48:16,506 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 12:48:16,531 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 12:48:22,506 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 12:48:22,516 - octoprint.server.util.sockjs - WARNING - Could not send message to client ::ffff:192.168.0.37: object of type 'NoneType' has no len()
2019-01-03 12:48:22,522 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 12:48:22,545 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 12:48:49,252 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 12:48:54,506 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 12:48:55,220 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 12:48:55,240 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 12:52:47,382 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2019-01-03 13:03:55,312 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 13:03:55,319 - tornado.application - ERROR - Exception in callback None
Traceback (most recent call last):
  File "/home/pi/oprint/local/lib/python2.7/site-packages/tornado/ioloop.py", line 836, in start
    fd_obj, handler_func = self._handlers[fd]
KeyError: 24
2019-01-03 13:03:55,329 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 13:03:55,340 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 13:03:55,349 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 13:03:55,356 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 13:03:55,365 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 13:03:55,376 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 13:03:55,434 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 13:03:55,461 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 13:03:55,488 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 13:04:01,506 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 13:04:01,514 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 13:04:01,529 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 13:04:01,592 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 13:04:07,506 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 13:04:07,515 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 13:07:47,384 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2019-01-03 13:18:56,263 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 13:18:56,329 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 13:18:57,209 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 13:18:57,275 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 13:18:57,430 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 13:18:57,458 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 13:19:02,506 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 13:19:02,514 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 13:22:47,385 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2019-01-03 13:23:56,848 - tornado.access - WARNING - 405 PROPFIND / (127.0.0.1) 2.99ms
2019-01-03 13:24:13,275 - tornado.access - WARNING - 405 PROPFIND /home/ (127.0.0.1) 2.98ms
2019-01-03 13:24:22,264 - tornado.access - WARNING - 405 PROPFIND / (127.0.0.1) 3.22ms
2019-01-03 13:24:59,570 - tornado.access - WARNING - 405 PROPFIND /pi/ (127.0.0.1) 2.98ms
2019-01-03 13:25:18,743 - tornado.access - WARNING - 405 PROPFIND / (127.0.0.1) 3.30ms
2019-01-03 13:30:11,320 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 13:30:11,326 - tornado.application - ERROR - Exception in callback None
Traceback (most recent call last):
  File "/home/pi/oprint/local/lib/python2.7/site-packages/tornado/ioloop.py", line 836, in start
    fd_obj, handler_func = self._handlers[fd]
KeyError: 25
2019-01-03 13:30:11,337 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 13:30:11,346 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 13:30:11,356 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 13:30:11,363 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 13:30:11,371 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 13:30:22,985 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 13:30:23,045 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 13:30:24,625 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 13:30:26,283 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 13:30:27,925 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 13:30:28,054 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 13:30:28,086 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 13:30:28,698 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 13:30:29,349 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 13:30:33,506 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 13:30:41,285 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 13:30:41,307 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 13:30:41,413 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 13:30:41,452 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 13:30:41,499 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 13:30:44,329 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 13:30:49,506 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 13:30:49,518 - octoprint.server.util.sockjs - WARNING - Could not send message to client ::ffff:192.168.0.37: object of type 'NoneType' has no len()
2019-01-03 13:30:49,524 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 13:30:49,543 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37
2019-01-03 13:31:01,804 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.0.37
2019-01-03 13:31:01,826 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.0.37

You should probably try Refreshing/Reloading your browser.

I refreshed my browser in between everything I tried, sometimes restarting too.

That error is amazingly consistent!

Traceback (most recent call last):
  File "/home/pi/oprint/local/lib/python2.7/site-packages/tornado/ioloop.py", line 836, in start
    fd_obj, handler_func = self._handlers[fd]
KeyError: 25

..I don't know why, though. It's clear the file descriptor doesn't exist, but I have no idea why. Have you tried upgrading to 1.3.10 and seeing if that clears it up (or makes it worse)?

I tried upgrading, it didn't make it any better or worse.
I am still seeing that error, with the only change being the line number referenced:

2019-01-03 21:28:50,455 - tornado.application - ERROR - Exception in callback None
Traceback (most recent call last):
  File "/home/pi/oprint/local/lib/python2.7/site-packages/tornado/ioloop.py", line 887, in start
    fd_obj, handler_func = self._handlers[fd]
KeyError: 29

on a fresh reflash of the SD card, first thing is do sudo apt update && sudo apt full-upgrade. This will update raspbian to ensure it has all the latest packages. also, disable IPV6 on the Pi. IPV6 seems to cause more problems than anything. (In config.txt add ipv6.disable=1 at the end) don't add any return or anything as that file has to be a single line. Edit it with nano or vi.

I did a fresh reflash of the SD card, added the "ipv6.disable=1" line to the config file, and ran the update statements that you provided. I am still getting the same message from the OctoPrint web browser.

Here is the most recent log file:
octoprint.log (15.7 KB)

That is strange... Hopefully someone can come up with something

IOLoop is from Tornado, it handles asynchronous sockets. It seems to be complaining that the 29th key in an array (_handlers[]) isn't happy. So maybe it walked the array and discovered that fd_obj was null or that handler_func was set to None.

Here's the code in question:

My normal advice would be to tell you to run in Safe Mode but it looks like you're vanilla already.

Perhaps an OctoPrint forced re-install in-place is what this needs. You'd need to first do a source ~/oprint/bin/activate to be in the right zone for this.

So, it appears that the issue is between my computer and the network, and has nothing to do with the Rasberry Pi or OctoPrint.
My computer keeps showing up on the network under the wrong name.
I managed to get up and running, but I think the router is going to need to be replaced soon.

1 Like

I have the same problem. It usually happens when I have a power failure. I reboot the Raspberry Pi again and the browser can then see it. I have no idea what the problem is as I am not that technical, I just know the solution.

Yeah same here. That screen just comes out of nowhere all the time

The "Server is Offline" page is probably served up by haproxy on port 80 and it's trying to say that OctoPrint on port 5000 is unavailable.

The time I usually see this is when I:

  • Start the Pi
  • Login via the web interface
  • ssh into the Pi
  • Do a sudo service octoprint restart (I'm a coder so I do this from time to time)

Back in the browser it tries to do something and determine that the service on port 5000 is now not responding. Technically haproxy is still running and talking to the browser so things look pleasant enough; you're not presented with a terse 404 style of message.

And then next, this screen gets promoted to a Reconnect button version of same since it needs to refresh the browser's pageโ€”it knows that the service is available again. Often, it will do all this automatically if you're patient.

But if it never promotes to the Reconnect screen then the service didn't come back up. An often-seen reason for this is a poorly-formatted ~/.octoprint/config.yaml file. Formatting is everything at the start of each line. Typically, a plugin will try to update the file and something will go wrong. (Sometimes, someone will be in there trying to add a custom control as described in the documentation and make a formatting mistake.) My general guidance would be to...

  • not use tabs
  • many lines begins with a multiple of four spaces which forms a single level of indentation

PLEASE do not do this...
It corrupts the SD card

This is from the TO one year ago. The actual problem started one day ago... :wink: