The driver you would need is for the Postgres database. Here's a link from our OnlineHelp for Linux:
with this one note:
Important: You must install the PostgreSQL driver if you want to use the built-in administrative views.
Interesting that the drivers aren't part of the base Tableau Server install.
There is a better link than the one I first provided:
with the following snippet:
Viewing built-in administrative views. With this release of Tableau Server on Linux, you must install PostgreSQL drivers manually, and the administrative views depend on these. Confirm that you have installed the drivers necessary by accessing the built-in administrative views. For more information, see Administrative Views.
Thanks all for the help. I must have missed it when reading through it.