---
title: Add mutual TLS to Prometheus endpoints
source: https://docs.newrelic.com/docs/infrastructure/prometheus-integrations/install-configure-openmetrics/add-mutual-tls-prometheus-endpoints
---

You can configure mutual TLS authentication when needed for the endpoints in your Prometheus OpenMetrics integration with New Relic. Add `tls_config` to your configuration file for Docker, as explained in this example.

## Add secret to config file [#mutual-tls-authentication]

Recommendation: Put the CA bundle, key, and cert files in a secret, and include them in the Prometheus OpenMetrics integration's container.

Mutual TLS authentication is limited to a static list of URLs. To configure endpoints that require MTLS authentication, follow this example:

```yml
targets:
  - description: "Secure etcd example"
    urls: ["https://123.456.7.1:2379", "https://123.456.7.2:2379"]
    tls_config:
      ca_file_path: "/etc/etcd/etcd-client-ca.crt"
      cert_file_path: "/etc/etcd/etcd-client.crt"
      key_file_path: "/etc/etcd/etcd-client.key"
transformations: 
  ...
```