> ## Documentation Index
> Fetch the complete documentation index at: https://docs.cognite.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Troubleshooting

> Find information to help you troubleshoot issues using Cognite Data Fusion (CDF) as a data source in Grafana.

<a id="Bad-Gateway-when-setting-up-the-API-Host-in-the-Grafana-instance" />

## <span translate="no">Bad Gateway</span> error when setting up the <span translate="no">API Host</span>

**Symptom**

When selecting <span class="ui-element">Save & test</span> in the <span translate="no">CDF</span> plugin configuration, the user gets a <span translate="no">**Bad Gateway**</span> error. The <span class="ui-element">developer</span> tab in <span translate="no">Grafana</span> has a 502 error in the <span translate="no">network</span> tab.

**Causes**

The <span class="ui-element">API Host</span> in the setup is wrong, but the user only gets the <span class="ui-element">Bad Gateway</span> error message.

**Fixes**

Check that the <span class="ui-element">API Host</span> field has a valid <span translate="no">Cognite</span> hostname.

* If the project uses the default multi-tenant cluster (`api.cognitedata.com`), keep the default value and don't change the hostname.
* If the project uses another cluster like, `westeurope-1.cognitedata.com`, change the hostname to point to the API server for the cluster.
* If you're unsure, use the default hostname.
* Do not use `https://` or trailing slashes `/` in the <span class="ui-element">API Host</span> field.