Hi

To backup a Tableau Server, please complete the following steps as per article.

Back Up the Tableau Data

This will create a single file that holds the data managed by Tableau Server consisting of Tableau's own PostgreSQL database, which contains workbook and user metadata, data extract (.tde) files, and configuration data.

You can also export an individual site, if this is more useful to you

Import or Export a Site

Hope this helps

Glen