Please check you have installed all the support drivers needed for tableau server.
Ex: Cloudera Driver for Apache hive and impala if youre using cloudera hadoop connectivity for datasources.
Incase If tableau server configured with high availability then drivers should be installed in all worker machines as well.
Did you solved the problem?
Thanks for following up.
We are still having this issue. We tried your suggestion regarding drivers and few others. But no luck so far.