Hi Network Administrator, I want to help you with this question.
The Azure file sync service is designed to be bidirectional. So it is not possible to have data out of sync. If you delete one file it will sync the change on the other site.
Also, I wouldn't recommend disabling the connectors after uploading the files if this was not your intention.
In this case, I prefer to use Azure Data Factory. Here you can upload files from On-Prem locations to Azure File Share and changes will not be syncronized.
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