Connecting to Printer failed but not failed

After an update to the latest version I can not connect to my Anet A8 printer any more via browser gui.

With the use of the telegram app / plugin I can connect, but nothing more.

The Browser-GUI shows me "Disconnect" all the time - independent if connected/disconnect via telegram!

what can I do? (the installation is nearly brand new because of a sd card death after updating).

Sadly you deleted the template when opened this thread.
So help could take a while because we need to guess what maybe could be wrong.
So many important informations are missing.

1 Like

Which template?
The one prefilled on adding a new question in the input field?
I have no camera yet, i wrote about the version "latest version".
There are no suitable logs as far as I can see.

What else did you need to help me?

When you open a thread in Get Help, the initial post is filled with this template:



<!-- ~~~~~ Filling this out properly makes it WAY more likely to get help quickly ~~~~~ -->

**What is the problem?**

**What did you already try to solve it?**

**Logs** (`octoprint.log`, `serial.log` or output on terminal tab *at a minimum*, browser error console if UI issue ... **no logs, no support!**)

**Additional information about your setup** (OctoPrint version, OctoPi version, printer, firmware, browser, operating system, ... **as much data as possible**)

As I did as I thought.

Most important are the log files that are asked for

@FlyingEaglE
First, text in blue is a link and when you click on it, valuable instructions will magically appear.

Second, "latest" is not a version number.

Third, we know you have an "Anet A8 printer", a "browser", and "the telegram app". Beyond that we know nothing, we will assume you have OctoPrint (of unknown origin) because you found these forums but we don't know its version number, what it is hosted on (type, model, version, etc.).

Last, here's a few more links for you to study:

Need help? Read this first! Remember to provide version numbers, relevant log files and general information about your setup. Problem solved? Mark the solution! WE NEED LOGS TO HELP YOU!

octoprint.log after reloading the page and clicking on the connect-button that always shows "disconnecting".

2020-07-08 17:45:19,822 - octoprint.plugins.dashboard - INFO - cmd_results: 9V
2020-07-08 17:45:21,753 - octoprint.server.util.flask - INFO - Passively logging in user lw from ::ffff:192.168.3.104
2020-07-08 17:45:21,756 - octoprint.access.users - INFO - Cleaning up user session F647AABDC76E41438827C26CC126E256 for user lw
2020-07-08 17:45:21,757 - octoprint.access.users - INFO - Logged out user: lw
2020-07-08 17:45:21,759 - octoprint.access.users - INFO - Cleaning up user session 33800B4964BF4DCB8428E886C5FE9B73 for user lw
2020-07-08 17:45:21,762 - octoprint.server.util.sockjs - INFO - User lw logged out, logging out on socket
2020-07-08 17:45:21,770 - octoprint.access.users - INFO - Logged out user: lw
2020-07-08 17:45:21,771 - octoprint.access.users - INFO - Logged in user: lw
2020-07-08 17:45:22,051 - octoprint.server.util.flask - INFO - Passively logging in user lw from ::ffff:192.168.3.102
2020-07-08 17:45:22,053 - octoprint.access.users - INFO - Cleaning up user session F647AABDC76E41438827C26CC126E256 for user lw
2020-07-08 17:45:22,055 - octoprint.access.users - INFO - Logged out user: lw
2020-07-08 17:45:22,058 - octoprint.access.users - INFO - Logged in user: lw
2020-07-08 17:45:22,099 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.3.104
2020-07-08 17:45:22,151 - octoprint.server.util.sockjs - INFO - User lw logged in on the socket from client ::ffff:192.168.3.102
2020-07-08 17:45:23,105 - octoprint.plugins.dashboard - INFO - cmd_results: 9V
2020-07-08 17:45:25,587 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.3.104
2020-07-08 17:45:26,075 - octoprint.server.util.flask - INFO - Passively logging in user lw from ::ffff:192.168.3.104
2020-07-08 17:45:26,080 - octoprint.access.users - INFO - Logged in user: lw
2020-07-08 17:45:26,181 - octoprint.plugins.dashboard - INFO - cmd_results: 9V
2020-07-08 17:45:28,422 - octoprint.plugins.announcements - INFO - Loaded channel _important from https://octoprint.org/feeds/important.xml in 0.2s
2020-07-08 17:45:29,076 - octoprint.plugins.announcements - INFO - Loaded channel _releases from https://octoprint.org/feeds/releases.xml in 0.19s
2020-07-08 17:45:31,439 - octoprint.plugins.dashboard - INFO - cmd_results: 9V
2020-07-08 17:45:31,614 - octoprint.plugins.announcements - INFO - Loaded channel _blog from https://octoprint.org/feeds/octoblog.xml in 0.21s
2020-07-08 17:45:31,971 - octoprint.plugins.announcements - INFO - Loaded channel _plugins from https://plugins.octoprint.org/feed.xml in 0.2s
2020-07-08 17:45:32,370 - octoprint.plugins.announcements - INFO - Loaded channel _octopi from https://octoprint.org/feeds/octopi.xml in 0.19s
2020-07-08 17:45:33,133 - octoprint.plugins.pluginmanager - INFO - Loaded plugin repository data from https://plugins.octoprint.org/plugins.json
2020-07-08 17:45:36,609 - octoprint.plugins.dashboard - INFO - cmd_results: 9V
2020-07-08 17:45:36,769 - octoprint.plugins.pluginmanager - INFO - Loaded plugin notices data from https://plugins.octoprint.org/notices.json
2020-07-08 17:45:39,782 - octoprint.plugins.dashboard - INFO - cmd_results: 9V
2020-07-08 17:45:41,228 - octoprint.util.pip - INFO - Using "/home/pi/oprint/bin/python2 -m pip" as command to invoke pip
2020-07-08 17:45:41,556 - octoprint.util.pip - INFO - Using "/home/pi/oprint/bin/python2 -m pip" as command to invoke pip
2020-07-08 17:45:41,663 - octoprint.util.pip - INFO - Using "/home/pi/oprint/bin/python2 -m pip" as command to invoke pip
2020-07-08 17:45:41,765 - octoprint.util.pip - INFO - Using "/home/pi/oprint/bin/python2 -m pip" as command to invoke pip
2020-07-08 17:45:41,902 - octoprint.util.pip - INFO - Using "/home/pi/oprint/bin/python2 -m pip" as command to invoke pip
2020-07-08 17:45:42,852 - octoprint.plugins.dashboard - INFO - cmd_results: 9V

Versions

Aktuelle Versionen
**OctoPrint: 1.4.0 **
**Installiert: 1.4.0**
**Verf├╝gbar: 1.4.0 (stable)**
Release Notes: https://github.com/OctoPrint/OctoPrint/releases/tag/1.4.0
Cost Plugin: 0.1.3 
Installiert: 0.1.3
Verf├╝gbar: 0.1.3: The Missing Release
Release Notes: https://github.com/jasiek/OctoPrint-Cost/releases/tag/0.1.3
Dashboard Plugin: 1.14.0 
Installiert: 1.14.0
Verf├╝gbar: 1.13.0
Release Notes: https://github.com/StefanCohen/OctoPrint-Dashboard/releases/tag/1.13.0
DetailedProgress Plugin: 0.2.5 
Installiert: 0.2.5
Verf├╝gbar: 0.2.5
Release Notes: https://github.com/tpmullan/OctoPrint-DetailedProgress/releases/tag/0.2.5
Dragon Order: 0.1.4 
Installiert: 0.1.4
Verf├╝gbar: 0.1.4
Release Notes: https://github.com/jneilliii/OctoPrint-DragonOrder/releases/tag/0.1.4
Fullscreen Plugin: 0.0.5 
Installiert: 0.0.5
Verf├╝gbar: 0.0.5
Release Notes: https://github.com/BillyBlaze/OctoPrint-FullScreen/releases/tag/0.0.5
GCode System Commands: 1.0.1 
Installiert: 1.0.1
Verf├╝gbar: 1.0.1
Release Notes: https://github.com/kantlivelong/OctoPrint-GCodeSystemCommands/releases/tag/1.0.1
Gcodebar Plugin: 0.1.5 
Installiert: 0.1.5
Verf├╝gbar: Python3 compability
Release Notes: https://github.com/mtowara/OctoPrint-Gcodebar/releases/tag/0.1.5
Heater Timeout Plugin: 0.0.3 
Installiert: 0.0.3
Verf├╝gbar: -
Marlin Flasher: 0.3.5 
Installiert: 0.3.5
Verf├╝gbar: 0.3.5
Release Notes: https://github.com/Renaud11232/OctoPrint-Marlin-Flasher/releases/tag/0.3.5
Navbar Temperature Plugin: 0.14 
Installiert: 0.14
Verf├╝gbar: 0.14 Milestone release
Release Notes: https://github.com/imrahil/OctoPrint-NavbarTemp/releases/tag/0.14
OctoPrint-BedLevelingWizard: 0.2.4 
Installiert: 0.2.4
Verf├╝gbar: 0.2.4
Release Notes: https://github.com/jneilliii/OctoPrint-BedLevelingWizard/releases/tag/0.2.4
Octoprint-Display-ETA: 1.1.1 
Installiert: 1.1.1
Verf├╝gbar: Version 1.1.1 - Fix for issue #9
Release Notes: https://github.com/AlexVerrico/Octoprint-Display-ETA/releases/tag/1.1.1
OctoPrint-WideScreen: 0.1.2 
Installiert: 0.1.2
Verf├╝gbar: 0.1.3
Release Notes: https://github.com/jneilliii/OctoPrint-WideScreen/releases/tag/0.1.3
Shutdown Printer: 1.0.9 
Installiert: 1.0.9
Verf├╝gbar: 1.0.8
Release Notes: https://github.com/devildant/OctoPrint-ShutdownPrinter/releases/tag/1.0.8
Sidebar Temp Graph: 0.1.5 
Installiert: 0.1.5
Verf├╝gbar: 0.1.5
Release Notes: https://github.com/jneilliii/OctoPrint-SideBarTempGraph/releases/tag/0.1.5
Sidebar Webcam: 0.1.8 
Installiert: 0.1.8
Verf├╝gbar: 0.1.8
Release Notes: https://github.com/quanticchaos/OctoPrint-Webcamsb/releases/tag/0.1.8
Slicer: 1.4.3 
Installiert: 1.4.3
Verf├╝gbar: Out of maintenance.
Release Notes: https://github.com/kennethjiang/OctoPrint-Slicer/releases/tag/1.4.3
Tab Order: 0.5.8 
Installiert: 0.5.8
Verf├╝gbar: 0.5.8
Release Notes: https://github.com/jneilliii/OctoPrint-TabOrder/releases/tag/0.5.8
Telegram Notifications: 1.5.0 
Installiert: 1.5.0
Verf├╝gbar: 1.5.0 - New features and bug fix
Release Notes: https://github.com/fabianonline/OctoPrint-Telegram/releases/tag/1.5.0
Tempsgraph Plugin: 0.3.6 
Installiert: 0.3.6
Verf├╝gbar: Fixes for octoprint 1.4.0
Release Notes: https://github.com/1r0b1n0/OctoPrint-Tempsgraph/releases/tag/0.3.6
Touchtest Plugin: 0.1.1 
Installiert: 0.1.1
Verf├╝gbar: -
TouchUI: 0.3.14 
Installiert: 0.3.14
Verf├╝gbar: 0.3.14
Release Notes: https://github.com/BillyBlaze/OctoPrint-TouchUI/releases/tag/0.3.14

After trying to logout and login again (without closing the browser that is not possible at the moment because of reasons)


2020-07-08 17:50:05,140 - octoprint.access.users - INFO - Logged out user: lw
2020-07-08 17:50:06,815 - tornado.access - WARNING - 403 GET /api/settings (::ffff:192.168.3.104) 419.51ms
2020-07-08 17:50:06,953 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.3.104
2020-07-08 17:50:07,827 - octoprint.plugins.dashboard - INFO - cmd_results: 9V
2020-07-08 17:50:07,974 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.3.104
2020-07-08 17:50:10,903 - octoprint.plugins.dashboard - INFO - cmd_results: 9V
2020-07-08 17:50:13,964 - octoprint.plugins.dashboard - INFO - cmd_results: 9V
2020-07-08 17:50:17,025 - octoprint.plugins.dashboard - INFO - cmd_results: 9V
2020-07-08 17:50:20,085 - octoprint.plugins.dashboard - INFO - cmd_results: 9V
2020-07-08 17:50:23,147 - octoprint.plugins.dashboard - INFO - cmd_results: 9V
2020-07-08 17:50:26,209 - octoprint.plugins.dashboard - INFO - cmd_results: 9V
2020-07-08 17:50:29,272 - octoprint.plugins.dashboard - INFO - cmd_results: 9V
2020-07-08 17:50:32,333 - octoprint.plugins.dashboard - INFO - cmd_results: 9V
2020-07-08 17:50:35,395 - octoprint.plugins.dashboard - INFO - cmd_results: 9V
2020-07-08 17:50:38,457 - octoprint.plugins.dashboard - INFO - cmd_results: 9V
2020-07-08 17:50:41,099 - octoprint.access.users - INFO - Logged in user: lw
2020-07-08 17:50:41,106 - octoprint.server.api - INFO - Actively logging in user lw from ::ffff:192.168.3.104
2020-07-08 17:50:41,189 - octoprint.server.util.flask - INFO - Passively logging in user lw from ::ffff:192.168.3.104
2020-07-08 17:50:41,191 - octoprint.access.users - INFO - Logged in user: lw
2020-07-08 17:50:41,526 - octoprint.plugins.dashboard - INFO - cmd_results: 9V
2020-07-08 17:50:41,624 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.3.104
2020-07-08 17:50:44,289 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.3.104
2020-07-08 17:50:44,701 - octoprint.plugins.dashboard - INFO - cmd_results: 9V
2020-07-08 17:50:45,112 - tornado.access - WARNING - 403 GET /api/settings (::ffff:192.168.3.104) 430.99ms
2020-07-08 17:50:47,764 - octoprint.plugins.dashboard - INFO - cmd_results: 9V

Sencond try to relogin, and logged in successfully


2020-07-08 17:52:05,915 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.3.104
2020-07-08 17:52:06,523 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.3.104
2020-07-08 17:52:07,414 - octoprint.plugins.dashboard - INFO - cmd_results: 9V
2020-07-08 17:52:08,756 - octoprint.access.users - INFO - Logged in user: lw
2020-07-08 17:52:08,761 - octoprint.server.api - INFO - Actively logging in user lw from ::ffff:192.168.3.104
2020-07-08 17:52:08,887 - octoprint.server.util.flask - INFO - Passively logging in user lw from ::ffff:192.168.3.104
2020-07-08 17:52:08,890 - octoprint.access.users - INFO - Logged in user: lw
2020-07-08 17:52:09,258 - octoprint.server.util.sockjs - INFO - Client connection closed: ::ffff:192.168.3.104
2020-07-08 17:52:10,478 - octoprint.plugins.dashboard - INFO - cmd_results: 9V
2020-07-08 17:52:10,706 - octoprint.server.util.sockjs - INFO - New connection from client: ::ffff:192.168.3.104
2020-07-08 17:52:11,013 - octoprint.server.util.flask - INFO - Passively logging in user lw from ::ffff:192.168.3.104
2020-07-08 17:52:11,017 - octoprint.access.users - INFO - Logged in user: lw
2020-07-08 17:52:14,519 - octoprint.plugins.dashboard - INFO - cmd_results: 9V
2020-07-08 17:52:15,726 - tornado.access - WARNING - 400 GET /plugin/marlin_flasher/board/details (::ffff:192.168.3.104) 354.71ms
2020-07-08 17:52:15,827 - tornado.access - WARNING - 400 GET /plugin/marlin_flasher/firmware (::ffff:192.168.3.104) 91.71ms
2020-07-08 17:52:15,949 - octoprint.plugins.shutdownprinter - INFO - eventView
2020-07-08 17:52:16,726 - octoprint.plugins.shutdownprinter - INFO - eventView
2020-07-08 17:52:17,591 - octoprint.plugins.dashboard - INFO - cmd_results: 9V

I noticed the small icon above that show under-voltage ... I have never seen it before ... it is blinking.
The power-supply is connected to a USB-Port with 3.5A !!!
But I can not imagine that this is the problem, because I can connect via telegram plugin.

Printer Firmware: Marlin 1.1.9 (need newer HEX but can not compile for some reasons)

If the icon is blinking it means your pi is actively throttled due to undervoltage. No matter whether your power supply says it's up to specs, it isn't. Your pi is not getting enough juice and that may well be the reason for your issues. Get it a power supply that is up to spec.

Once you get the power supply issue solved, we will need a serial.log. Enable it, attempt to connect to the printer, and then post the log file.

It is possible that your printer is drawing power from its USB connection. See https://community.octoprint.org/t/put-tape-on-the-5v-pin-why-and-how/13574 to fix that.

You have a fair number of plugins so should try to connect in safe mode as well.

after starting upp with auto connect on

2020-07-08 20:57:44,365 - Connecting to: /dev/ttyUSB0
2020-07-08 20:57:44,389 - Changing monitoring state from "Offline" to "Opening serial port"
2020-07-08 20:57:44,411 - Connected to: Serial<id=0x6eeb5e30, open=True>(port='/dev/ttyUSB0', baudrate=115200, bytesize=8, parity='N', stopbits=1, timeout=10.0, xonxoff=False, rtscts=False, dsrdtr=False), starting monitor
2020-07-08 20:57:44,412 - Starting baud rate detection...
2020-07-08 20:57:44,413 - Changing monitoring state from "Opening serial port" to "Detecting baudrate"
2020-07-08 20:57:46,528 - Trying baudrate: 115200
2020-07-08 20:57:47,127 - Recv: start
2020-07-08 20:57:47,160 - Send: N0 M110 N0*125
2020-07-08 20:57:47,235 - Changing monitoring state from "Detecting baudrate" to "Operational"
2020-07-08 20:57:47,278 - Recv: echo: External Reset
2020-07-08 20:57:47,284 - Recv: Marlin 1.1.9
2020-07-08 20:57:47,300 - Recv:
2020-07-08 20:57:47,342 - Recv: echo: Last Updated: 2018-07-31 | Author: (Bob Kuhn, Anet config)
2020-07-08 20:57:47,572 - Recv: echo:Compiled: Aug 17 2018
2020-07-08 20:57:47,573 - Send: N0 M110 N0*125
2020-07-08 20:57:47,584 - Recv: echo: Free Memory: 12236  PlannerBufferBytes: 1232
2020-07-08 20:57:47,744 - Recv: echo:EEPROM version mismatch (EEPROM=? Marlin=V55)
2020-07-08 20:57:47,789 - Recv: echo:Hardcoded Default Settings Loaded
2020-07-08 20:57:47,931 - Recv: ok
2020-07-08 20:57:47,942 - Recv: ok
2020-07-08 20:57:48,122 - Send: N1 M115*39
2020-07-08 20:57:48,139 - Send: N2 M21*18
2020-07-08 20:57:48,240 - Recv: FIRMWARE_NAME:Marlin 1.1.9 (Github) SOURCE_CODE_URL:https://github.com/MarlinFirmware/Marlin PROTOCOL_VERSION:1.0 MACHINE_TYPE:3D Printer EXTRUDER_COUNT:1 UUID:cede2a2f-41a2-4748-9b12-c55c62f367ff
2020-07-08 20:57:48,351 - Recv: Cap:SERIAL_XON_XOFF:0
2020-07-08 20:57:48,373 - Recv: Cap:EEPROM:1
2020-07-08 20:57:48,402 - Recv: Cap:VOLUMETRIC:1
2020-07-08 20:57:48,406 - Recv: Cap:AUTOREPORT_TEMP:1
2020-07-08 20:57:48,428 - Recv: Cap:PROGRESS:0
2020-07-08 20:57:48,434 - Recv: Cap:PRINT_JOB:1
2020-07-08 20:57:48,455 - Recv: Cap:AUTOLEVEL:0
2020-07-08 20:57:48,508 - Recv: Cap:Z_PROBE:0
2020-07-08 20:57:48,560 - Recv: Cap:LEVELING_DATA:0
2020-07-08 20:57:48,584 - Recv: Cap:BUILD_PERCENT:0
2020-07-08 20:57:48,600 - Recv: Cap:SOFTWARE_POWER:0
2020-07-08 20:57:48,610 - Recv: Cap:TOGGLE_LIGHTS:0
2020-07-08 20:57:48,614 - Recv: Cap:CASE_LIGHT_BRIGHTNESS:0
2020-07-08 20:57:48,618 - Recv: Cap:EMERGENCY_PARSER:0
2020-07-08 20:57:48,709 - Recv: Cap:AUTOREPORT_SD_STATUS:0
2020-07-08 20:57:48,730 - Recv: Cap:THERMAL_PROTECTION:1
2020-07-08 20:57:48,861 - Recv: ok
2020-07-08 20:57:48,925 - Send: M117 IP 192.168.3.105
2020-07-08 20:57:52,394 - Recv: echo:SD init fail
2020-07-08 20:57:52,412 - Recv: ok
2020-07-08 20:57:52,420 - Send: M155 S2
2020-07-08 20:57:52,429 - Recv: ok
2020-07-08 20:57:52,443 - Send: M105
2020-07-08 20:57:52,472 - Recv: ok
2020-07-08 20:57:52,491 - Recv: ok T:24.00 /0.00 B:24.41 /0.00 @:0 B@:0
2020-07-08 20:57:54,432 - Recv:  T:24.00 /0.00 B:24.31 /0.00 @:0 B@:0
2020-07-08 20:57:56,433 - Recv:  T:24.00 /0.00 B:24.31 /0.00 @:0 B@:0
2020-07-08 20:57:58,433 - Recv:  T:24.00 /0.00 B:24.31 /0.00 @:0 B@:0
2020-07-08 20:58:00,434 - Recv:  T:24.00 /0.00 B:24.28 /0.00 @:0 B@:0

disconnecting via gui

2020-07-08 21:56:24,076 - Connection closed, closing down monitor
2020-07-08 21:56:24,096 - Changing monitoring state from "Operational" to "Offline"

connecting via telegram

2020-07-08 21:56:55,706 - Connecting to: /dev/ttyUSB0
2020-07-08 21:56:56,081 - Changing monitoring state from "Offline" to "Opening serial port"
2020-07-08 21:56:56,549 - Connected to: Serial<id=0x670a3a50, open=True>(port='/dev/ttyUSB0', baudrate=115200, bytesize=8, parity='N', stopbits=1, timeout=10.0, xonxoff=False, rtscts=False, dsrdtr=False), starting monitor
2020-07-08 21:56:56,611 - Starting baud rate detection...
2020-07-08 21:56:56,613 - Changing monitoring state from "Opening serial port" to "Detecting baudrate"
2020-07-08 21:56:58,849 - Trying baudrate: 115200
2020-07-08 21:56:59,058 - Send: N0 M110 N0*125
2020-07-08 21:56:59,060 - Recv: start
2020-07-08 21:56:59,507 - Changing monitoring state from "Detecting baudrate" to "Operational"
2020-07-08 21:56:59,579 - Recv: echo: External Reset
2020-07-08 21:56:59,586 - Send: N0 M110 N0*125
2020-07-08 21:56:59,598 - Recv: Marlin 1.1.9
2020-07-08 21:56:59,630 - Recv:
2020-07-08 21:56:59,633 - Recv: echo: Last Updated: 2018-07-31 | Author: (Bob Kuhn, Anet config)
2020-07-08 21:56:59,636 - Recv: echo:Compiled: Aug 17 2018
2020-07-08 21:56:59,639 - Recv: echo: Free Memory: 12236  PlannerBufferBytes: 1232
2020-07-08 21:56:59,643 - Recv: echo:EEPROM version mismatch (EEPROM=? Marlin=V55)
2020-07-08 21:56:59,647 - Recv: echo:Hardcoded Default Settings Loaded
2020-07-08 21:56:59,650 - Recv: ok
2020-07-08 21:56:59,655 - Send: N1 M115*39
2020-07-08 21:56:59,656 - Recv: ok
2020-07-08 21:56:59,663 - Send: N2 M21*18
2020-07-08 21:56:59,678 - Recv: FIRMWARE_NAME:Marlin 1.1.9 (Github) SOURCE_CODE_URL:https://github.com/MarlinFirmware/Marlin PROTOCOL_VERSION:1.0 MACHINE_TYPE:3D Printer EXTRUDER_COUNT:1 UUID:cede2a2f-41a2-4748-9b12-c55c62f367ff
2020-07-08 21:56:59,699 - Recv: Cap:SERIAL_XON_XOFF:0
2020-07-08 21:56:59,704 - Recv: Cap:EEPROM:1
2020-07-08 21:56:59,707 - Recv: Cap:VOLUMETRIC:1
2020-07-08 21:56:59,710 - Recv: Cap:AUTOREPORT_TEMP:1
2020-07-08 21:56:59,716 - Recv: Cap:PROGRESS:0
2020-07-08 21:56:59,722 - Recv: Cap:PRINT_JOB:1
2020-07-08 21:56:59,724 - Recv: Cap:AUTOLEVEL:0
2020-07-08 21:56:59,727 - Recv: Cap:Z_PROBE:0
2020-07-08 21:56:59,731 - Recv: Cap:LEVELING_DATA:0
2020-07-08 21:56:59,733 - Recv: Cap:BUILD_PERCENT:0
2020-07-08 21:56:59,736 - Recv: Cap:SOFTWARE_POWER:0
2020-07-08 21:56:59,738 - Recv: Cap:TOGGLE_LIGHTS:0
2020-07-08 21:56:59,743 - Recv: Cap:CASE_LIGHT_BRIGHTNESS:0
2020-07-08 21:56:59,747 - Recv: Cap:EMERGENCY_PARSER:0
2020-07-08 21:56:59,749 - Recv: Cap:AUTOREPORT_SD_STATUS:0
2020-07-08 21:56:59,754 - Recv: Cap:THERMAL_PROTECTION:1
2020-07-08 21:56:59,756 - Recv: ok
2020-07-08 21:56:59,760 - Send: M117 IP 192.168.3.105
2020-07-08 21:57:03,933 - Recv: echo:SD init fail
2020-07-08 21:57:03,947 - Recv: ok
2020-07-08 21:57:03,953 - Recv: ok
2020-07-08 21:57:03,956 - Send: M155 S2
2020-07-08 21:57:03,962 - Recv: ok
2020-07-08 21:57:05,967 - Recv:  T:24.00 /0.00 B:24.00 /0.00 @:0 B@:0
2020-07-08 21:57:07,967 - Recv:  T:24.00 /0.00 B:24.00 /0.00 @:0 B@:0
2020-07-08 21:57:09,967 - Recv:  T:24.00 /0.00 B:24.00 /0.00 @:0 B@:0
2020-07-08 21:57:11,967 - Recv:  T:24.00 /0.00 B:24.00 /0.00 @:0 B@:0
2020-07-08 21:57:13,967 - Recv:  T:24.00 /0.00 B:24.00 /0.00 @:0 B@:0

but the ui do not change to online-mode!

The Pi worked with a 2A ps for aprox. 2 years, than after a year on pause later - but after a update - it wont?

Maybe there is a problem with the cable

The RPi probably "worked" in blissful ignorance. If there were random failures, they were dismissed (or missed).

Recent OS updates added the power check and now there are visible indicators and it can be monitored programmatically.

I think I found the power thief ... HDMI ... this wasn't connected before and by now for debug only ... once removed the icon is quiet ... and it is connecting via gui ... if this was the real issue than a message with a hint would be more then nice.

The undervoltage icon on click literally links you to an FAQ entry that tells you that undervoltage can cause these exact kind of problems.