Unknown Server Error" "hyper Api: Could Not Connect To The Hyper Server" Upon Resetting Hyper Installation

Published: 11 Apr 2020
Last Modified Date: 27 Nov 2020


When attempting to access published workbook on Tableau Server after resetting hyper installation, the following error occurs:

 "Unknown Server Error" "Hyper API: Could not connect to the Hyper server"


  • Tableau Server 


1. Ensure there are no ports being blocked on Tableau Server from ports 8000-9000
2. Verify if Hyper needs to be reinstalled and if the port needs to be reset to match the port on TSM.
3. Review the error for the port that is being requested by taking a netstat if it is listening.
4. Verify in the configuration of Tableau Server what port is designated by Tableau Server if it is different than the one Hyper is requesting.
5. Update the new configuration for the requested port to match the new installation:

tsm topology list-nodes (verify the node name to change)
tsm topology set-ports --node-name <node> --port-name hyper--port-value <port number>
tsm pending-changes apply


During the re-installation or change of ports on Tableau Server with Hyper, the port gets dynamically assigned. After reinstallation, the port will also need to be set in the topology.

Additional Information

A reinstallation of a port or changing around port settings  Tableau Server may create this issue if a user does not reset the configurations in reinstallations of specific parts of Tableau Server.
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