---
title: Using SSL connections to a data source
description: Enable TLS to upstream databases from Cube and, when required, inject custom CA bundles, client certificates, and private keys.
---

## Use case

Cube supports SSL-encrypted connections to various data sources. Please check
the documentation for a particular [data source][ref-config-db] for specific
instructions.

## Configuration

Generally, you can enable SSL via the [`CUBEJS_DB_SSL`](/reference/configuration/environment-variables#cubejs_db_ssl) environment variable.

### Cube Core

To enable SSL, set the [`CUBEJS_DB_SSL`](/reference/configuration/environment-variables#cubejs_db_ssl) environment variable to `true`. Cube can
also be configured to use custom connection settings. For example, to use a
custom certificate authority and certificates, you could do the following:

```dotenv
CUBEJS_DB_SSL_CA=/path/to/ssl/ca.pem
CUBEJS_DB_SSL_CERT=/path/to/ssl/cert.pem
CUBEJS_DB_SSL_KEY=/path/to/ssl/key.pem
```

You can also set the above environment variables to the contents of the PEM
files; for example:

```dotenv
CUBEJS_DB_SSL_CA="-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----"
```

### Cube Cloud

When setting up a new deployment, select the SSL checkbox when entering database
credentials:

<Frame>
  <img src="https://ucarecdn.com/a3edc952-41e2-4320-8c32-4524c85af5a6/" alt="Cube Cloud Database Connection Screen for Postgres" />
</Frame>

To use custom SSL certificates between Cube Cloud and your database server, go
to the **Configuration** tab in the **Settings** screen:

<Frame>
  <img src="https://ucarecdn.com/1fd4354c-deec-4fc1-bfdb-e05636021efd/" alt="Cube Cloud Database Connection Screen" />
</Frame>

Add the following environment variables:

| Environment Variable | Description                                                                                                                                                                                                 | Example                                  |
| -------------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ---------------------------------------- |
| [`CUBEJS_DB_SSL`](/reference/configuration/environment-variables#cubejs_db_ssl)      | If `true`, enables SSL encryption for database connections from Cube                                                                                                                                        | `true`, `false`                          |
| [`CUBEJS_DB_SSL_CA`](/reference/configuration/environment-variables#cubejs_db_ssl_ca)   | The contents of a CA bundle in PEM format, or a path to one. For more information, check the `options.ca` property for TLS Secure Contexts [in the Node.js documentation][nodejs-docs-tls-options]          | A valid CA bundle or a path to one       |
| [`CUBEJS_DB_SSL_CERT`](/reference/configuration/environment-variables#cubejs_db_ssl_cert) | The contents of an SSL certificate in PEM format, or a path to one. For more information, check the `options.cert` property for TLS Secure Contexts [in the Node.js documentation][nodejs-docs-tls-options] | A valid SSL certificate or a path to one |
| [`CUBEJS_DB_SSL_KEY`](/reference/configuration/environment-variables#cubejs_db_ssl_key)  | The contents of a private key in PEM format, or a path to one. For more information, check the `options.key` property for TLS Secure Contexts [in the Node.js documentation][nodejs-docs-tls-options]       | A valid SSL private key or a path to one |

[nodejs-docs-tls-options]:
  https://nodejs.org/docs/latest/api/tls.html#tls_tls_createsecurecontext_options
[ref-config-db]: /admin/connect-to-data/data-sources