Troubleshoot

Extension appears gray in tableau online but not in desktop

• Check the whitelisting in Tableau settings. The extension url needs to be whitelisted to be able to run in a Tableau online dashboard.

• Is the extension running behind a proxy? Be sure the proxy is not adding CSP (Content Security Policy) Headers to the request. To find out if this is the cause, open the developer tools in your browser and open the console tab. When there are red messages complaining about Content Security Policy, then this is the problem.

Running behind a Reversed Proxy and wrong domain in the trex file

• If you are running behind a reversed proxy and the domain in the trex is therefore showing the domain of the server instead of the public facing domain follow these steps.

• Open the config.yaml file in your installation folder.

• Add or update the host variable to the public facing domain.

• Restart the application.

• Download the trex file from yourdomain.com/trex

How to decrypt my keyfile?

Our application requires an unencrypted SSL key file. If you only have an encrypted key file, you must decrypt it using OpenSSL. Use the following command:

Windows

openssl.exe rsa -in encrypted.key -out decrypted.key

Linux

openssl rsa -in encrypted.key -out decrypted.key

Protocol mismatch after ppgrade – “Missing ALPN protocol” / allowHTTP1 eror

Symptoms

After upgrading to newer versions:

• Browser shows an error when accessing the extension endpoint (e.g. https://<host>:<port>/...)

• Error message may include: Missing ALPN Protocol, expected h2 to be available

• Environment includes a reverse proxy or load balancer in front of the extension service

Cause

A protocol mismatch between the reverse proxy / load balancer and the enterprise (self-hosted) environment.

Typical scenarios:

• The extension server is configured to run with HTTPS (TLS) enabled

• The reverse proxy / load balancer forwards traffic to the extension server using HTTP

• The extension server expects TLS/HTTP2, but receives plain HTTP/1.1

This results in the Missing ALPN Protocol error.

Resolution

Ensure protocol alignment between the reverse proxy / load balancer and the extension server.

• If the extension server is configured to run on HTTPS:

  • The reverse proxy / load balancer must forward traffic using HTTPS

  • Do not forward plain HTTP traffic to a TLS-enabled backend port

After correcting the configuration, restart the service if required and re-test access to the extension endpoint.