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Error "connection To Master Server Failed" Upon Testing The Agent Connection To The Master Server Url In The Registration


Published: 01 Jul 2020
Last Modified Date: 29 Jul 2020

Issue

When testing the Agent connection to the Master Server URL in the registration phase, the connection fails with the error below:

Master Server URL Connection Failure

 

Environment

  • Tableau Resource Monitoring Tool 2020.2.0
  • Windows Server

Resolution

Adjust the registry to include RSA/SHA512 and ECDSA/SHA512 

1. Open the registry with regedit.exe
2. Navigate to HKEY_LOCAL_MACHINE SYSTEM\CurrentControlSet\Control\Cryptography\Configuration\Local\SSL\00010003 Functions
3. Add the following entries on their own line below the existing values: RSA/SHA512 and ECDSA/SHA512
Cryptograhpy Functions
4. Save and reboot the machine for the changes to take effect. 
 

Cause

With RMT HTTPS enabled, the self-signed certificate uses the SHA512 algorithm and on machines without this supported, connections fail.

 

Additional Information

Windows Application Event Viewer logs may show a .NET error:

Exception: 
System.Net.Http.HttpRequestException: The SSL connection could not be established, see inner exception.
 ---> System.Security.Authentication.AuthenticationException: Authentication failed, see inner exception.
 ---> System.ComponentModel.Win32Exception (0x80090308): The token supplied to the function is invalid
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