Note this is a know bug - from ESRI customer care -
Please know that the issue you encounter is a known bug. I have attached this case to the bug and the details are as follows:
- Bug number: BUG-000133900
- Synopsis: The Field Map missing from Table to Table in ModelBuilder.
You should be able to check on the status of the bug in the My Esri page:
My Esri > My Organization > Support > Search for the BUG-#BUG-000133900.
Unfortunately, we do not have a workaround for the bug at this moment and the bug will be fixed in our upcoming releases (version 2.7). Until a new release is announced, I would suggest a downgrade to ArcGIS Pro 2.5 to restore the field mapping functionality.
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2.6.2 has partial functionality, fields can be removed from output but source mapping is still not functional until after the element has been run once.
This was used for the below work around.
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In this particular case I was able to work around the issue with the following process, though it is awkward.
- On a separate machine with a version of ArcPro that allowed the field map to appear we brought in a subset of the data that the server model was to process so that the field map could be set.
- That model was saved to a toolbox.
- Toolbox was copied to the server using 2.6.0
- Model was opened and the actual data source connected to the model and the output location was shared
- The field map settings have persisted
If you happen to find this I hope it is helpful.