From what I read, these settings are stored in the TN database, so only an API call will be able to change it. It would be nice to have an API tool we could use in situations like this.
We do have something. I'm not very proficient in its use but I can give a simple example.
From the TrueNAS UI - In the toolbar top right, go to settings -> API key
Click the API Docs button
This will open a new web page. In the top left, click RESTful 2.0, then click the Authorize button. Enter the same username/password you use to access the TrueNAS UI. Now you can use this page to view and change settings using the API
For example, to list all VMs, locate and expand the
GET /vm section. Then click the
Try it out button
Next click
Execute to list VMs, their current settings, and the VM ID that is needed for some other VM-related API calls. Notice the ID for my Home Assistant VM is
1
and the memory is currently set at
2GB
or
2048MB
Here I change the memory to
4GB
or
4096MB
After clicking
Execute, you can see in the response body, that the memory has been updated!
Hope this helps!