Strange textbox widget behavior

Dashboard
1

Hello,
Simple case: I subscribe a value from MQTT which is updated every ~40s. The string encodes a float, e. g "20.625" and forwards it to the text widget to display it with a fromat like this: {{msg.payload|number:1}}.
I have four of these constructs.

Now, the values vanish from time to time and reappear after several seconds. Seemingly, it is not synchronized with the mqtt events.
Has anybody observed the same? Is there a remedy against this?

BTW: I get numerous "connection lost" events in the web page on my mobile and sometimes on the desktop web browser. The behavior is the same on both.

2

I would suggest sticking a debug node after the MQTT IN node and see what happens there.

3

I did that. Just the expected values, no "", no null or so.
Can it be that on a "connection lost" all cached values are lost, too?

4

I would certainly address that issue first. What device are you running node red on and how did you install it?
Concentrate on the problem in the desktop as mobile devices have a different set of issues.
Are you running the desktop browser on the server running node red?

5

The server is a ubuntu 20.04. LTS VM running on ubuntu 20.04 LTS host in a virtual network bridge. It is command line only. The client is a current firefox browser on windows 10.
The mobile client is a current firefox browser on Android 11 on Samsung S20.
How can I track the connection issues? Where would I find an according log?

6

Stop node red and start it in a terminal, then you will see the log (it is also, by default, written to syslog). If you copy/paste the log from startup here it may give useful information. Also check the processor utilisation in the server to see if node-red is hogging the processor.

Are you using charts on the dashboard? If so then how many charts, how many lines on each, what time range do the charts show and how often are data points added to the charts? If you multiply all those together and it comes to a large number then that could be the problem.

7

It turned out to be difficult to stop node red. I used systemctl stop node-red, systemctl status node-red tells me its stopped and disabled. However, when I do "ps ax" I see a nodered process, when I kill it spawns anew. I could not find what spawns it.

But syslog shows something interesting:

Dec 16 05:24:39 alfred pm2[2644446]: [PM2] Process /usr/local/bin/node-red restored

Dec 16 05:24:39 alfred pm2[2644446]: │ node-red │ 0 │ N/A │ fork │ 2644464 │ online │ 0 │ 0s │ 0% │ 23.3 MB │ root │ disabled │

Dec 16 05:26:09 alfred pm2[2644560]: (node:2644560) Warning: Accessing non-existent property 'cat' of module exports inside circular dependency

Dec 16 05:26:09 alfred pm2[2644560]: (Use node --trace-warnings ... to show where the warning was created)

Dec 16 05:26:09 alfred pm2[2644560]: (node:2644560) Warning: Accessing non-existent property 'cd' of module exports inside circular dependency

Dec 16 05:26:09 alfred pm2[2644560]: (node:2644560) Warning: Accessing non-existent property 'chmod' of module exports inside circular dependency

Dec 16 05:26:09 alfred pm2[2644560]: (node:2644560) Warning: Accessing non-existent property 'cp' of module exports inside circular dependency

Dec 16 05:26:09 alfred pm2[2644560]: (node:2644560) Warning: Accessing non-existent property 'dirs' of module exports inside circular dependency

Dec 16 05:26:09 alfred pm2[2644560]: (node:2644560) Warning: Accessing non-existent property 'pushd' of module exports inside circular dependency

Dec 16 05:26:09 alfred pm2[2644560]: (node:2644560) Warning: Accessing non-existent property 'popd' of module exports inside circular dependency

Dec 16 05:26:09 alfred pm2[2644560]: (node:2644560) Warning: Accessing non-existent property 'echo' of module exports inside circular dependency

Dec 16 05:26:09 alfred pm2[2644560]: (node:2644560) Warning: Accessing non-existent property 'tempdir' of module exports inside circular dependency

Dec 16 05:26:09 alfred pm2[2644560]: (node:2644560) Warning: Accessing non-existent property 'pwd' of module exports inside circular dependency

Dec 16 05:26:09 alfred pm2[2644560]: (node:2644560) Warning: Accessing non-existent property 'exec' of module exports inside circular dependency

Dec 16 05:26:09 alfred pm2[2644560]: (node:2644560) Warning: Accessing non-existent property 'ls' of module exports inside circular dependency

Dec 16 05:26:09 alfred pm2[2644560]: (node:2644560) Warning: Accessing non-existent property 'find' of module exports inside circular dependency

Dec 16 05:26:09 alfred pm2[2644560]: (node:2644560) Warning: Accessing non-existent property 'grep' of module exports inside circular dependency

Dec 16 05:26:09 alfred pm2[2644560]: (node:2644560) Warning: Accessing non-existent property 'head' of module exports inside circular dependency

Dec 16 05:26:09 alfred pm2[2644560]: (node:2644560) Warning: Accessing non-existent property 'ln' of module exports inside circular dependency

Dec 16 05:26:09 alfred pm2[2644560]: (node:2644560) Warning: Accessing non-existent property 'mkdir' of module exports inside circular dependency

Dec 16 05:26:09 alfred pm2[2644560]: (node:2644560) Warning: Accessing non-existent property 'rm' of module exports inside circular dependency

Dec 16 05:26:09 alfred pm2[2644560]: (node:2644560) Warning: Accessing non-existent property 'mv' of module exports inside circular dependency

Dec 16 05:26:09 alfred pm2[2644560]: (node:2644560) Warning: Accessing non-existent property 'sed' of module exports inside circular dependency

Dec 16 05:26:09 alfred pm2[2644560]: (node:2644560) Warning: Accessing non-existent property 'set' of module exports inside circular dependency

Dec 16 05:26:09 alfred pm2[2644560]: (node:2644560) Warning: Accessing non-existent property 'sort' of module exports inside circular dependency

Dec 16 05:26:09 alfred pm2[2644560]: (node:2644560) Warning: Accessing non-existent property 'tail' of module exports inside circular dependency

Dec 16 05:26:09 alfred pm2[2644560]: (node:2644560) Warning: Accessing non-existent property 'test' of module exports inside circular dependency

Dec 16 05:26:09 alfred pm2[2644560]: (node:2644560) Warning: Accessing non-existent property 'to' of module exports inside circular dependency

Dec 16 05:26:09 alfred pm2[2644560]: (node:2644560) Warning: Accessing non-existent property 'toEnd' of module exports inside circular dependency

Dec 16 05:26:09 alfred pm2[2644560]: (node:2644560) Warning: Accessing non-existent property 'touch' of module exports inside circular dependency

Dec 16 05:26:09 alfred pm2[2644560]: (node:2644560) Warning: Accessing non-existent property 'uniq' of module exports inside circular dependency

Dec 16 05:26:09 alfred pm2[2644560]: (node:2644560) Warning: Accessing non-existent property 'which' of module exports inside circular dependency

Dec 16 05:26:09 alfred pm2[2644560]: [PM2] Process /usr/local/bin/node-red restored

This block of messages is repeated rougly every 90s. I do not know if this connected. It looks a some part tries to access /bin tools.

Regarding your questions: Load is 0.03 incl. mqtt mysql etc.
I do not have any charts.

8

It appears you are using pm2 for running node-red. The recommended method of installing node red is to use the Ubuntu/Debian/Pi install script, but I assume that you did not do this, or perhaps you have setup pm2 separately.

That doesn't sound good, but I don't know what it means, other than that there is something wrong somewhere. I could probably help more if node red was installed and run the more common way.

9

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