First thing you have to do to change the logging settings, after the first data sync has run successfully, is to go into your Magento1 backend, choose Configuration under System:
Choose the main site (the site you're attempting to affect) under CURRENT CONFIGURATION SCOPE:
Then, go to Settings => Logging Settings and set your preferred logging-settings and press Save Config:
The Logging settings include:
- Only Errors: Will log any errors that stops the module from working correctly
- Errror + Warn: Also logs warnings that are not causing the module to stop working, but might be necessary to fix as well.
- Error + Warn + Debug: Logs everything that the module interacts with. This should not be enabled on a live webshop as it will slow down the site.