Hello Sami,
1.) By default DataHub extracts
only metadata information from sources. Some ingestion sources
may extract actual data stored in the database for statistical/preview purposes but this is an opt-in feature that must be enabled on each ingestion recipe. See:
https://datahubproject.io/docs/metadata-ingestion/docs/dev_guides/sql_profiles
2.) By default DataHub GMS (the backend) uses port 8080, while the frontend uses 9002. You can configure ports at will.