Error javascript nodes with image output in server

We have a workflow that works correctly locally in KNIME AP (Version 5.1.2) in terms of running and writing results. When we upload it to the server (Version 4.16.6) with an executor (Version 5.1.2), with the necessary extensions to run the workflow, the executor crashes (Image 2) when it reaches JavaScript graph nodes with image output ports like the one shown below (Image 1). It is important to mention that this error had not occurred in previous versions of the server and the executor to the one currently installed (v4.16.6 and v5.1.2).

Imagen de WhatsApp 2023-12-06 a las 12.40.32_9c08afdf

(Image 1^, node configuration)

(Image 2^)

when we check the Logs of the executor we get the following error:

The test was done with Java Script nodes without image output port and it worked correctly. We also tested with a Python View node and it works correctly. How can we solve this problem? For us the use of these nodes is indispensable.

Finally, we attach the log that the server gave us with the tests and processes that were performed.

catalina.2023-12-06.log (183.1 KB)

Thank you very much.

Hi @slunah,

I have found no references to the mentioned issues within the provided log since the catalina log only covers the Apache Tomcat/KNIME Server application while the executor messages are stored in the localhost log files and the executor log.

But I found a main issue your installation is dealing with which should block you in using it in general: The https connector is not able to start at all, since most of the communication is done via this.

The error message indicates, that the provided password in the <apache_folder>/conf/server.xml for the Java Keystore is not the right one, could you please check and fix this first?
As sub-process instances of the connector are still running due to older restart attempts I would recommend to reboot the VM afterwards, so that the services are able to start again properly.


Hello, I attach the log of the localhost that refers to the executor, however, whenever the executor collapses we perform the restart of the virtual machine and the same error is still presented when you reach that node. This error only occurs with JS nodes that have image output.

localhost.2023-12-06.log (924.1 KB)

We performed the tests with a workflow that has 3 nodes and a table of 5 rows and 3 columns with data and still continues to generate the same problem when the “generate image” option is selected and the server crashes again.


We also validate the default path of the node where the generated image is saved and it does not have a weight greater than 30KB.


Thank you for the additional log file @slunah.

Unfortunately I haven’t found any messages reporting JavaScript issues.

Could you please check if the mentioned library is installed on your KNIME Server machine (if it is running on Linux): KNIME Server Installation Guide?

This is needed for the inbuilt chromium browser to process the image generation.


Hello, yes indeed we do have the extension installed on the server but the error still persists

We are shipping the KNIME Analytics Platform with a inbuilt Chromium engine since a while, which needs the linked package installed to work properly, this was the command for installing it:

sudo apt-get install libgtk-3-0

Could you please double check if this package already is installed on your OS?


Hello good afternoon, recently we installed the package mentioned in the previous answer, but the error persists and the executor crashes. Again I attach the logs generated by the executor and the server.

localhost.2023-12-11.log (243.2 KB)
catalina.2023-12-11.log (172.9 KB)

Hi @slunah ,

Sorry for the delayed reply, you would need to install xvfb and install the service as described here: KNIME Server Installation Guide

This service is now needed on Linux to successfully create images via javascript on the executor.


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