---
title: Add Security Headers
slug: bhdm/add-security-headers
createdAt: 2024-02-22T15:25:59.546Z
---

Complete the following steps to add new security headers to Belden Horizon Data Manager. 

# Security Header Directives

Refer to the following directives when completing the steps below. 

```shell
add_header Content-Security-Policy "default-src 'self' https://static.zdassets.com https://ekr.zdassets.com;";
add_header X-Frame-Options SAMEORIGIN;
add_header X-XSS-Protection "1; mode=block";
add_header X-Content-Type-Options nosniff;
add_header Strict-Transport-Security "max-age=31536000; includeSubDomains; preload; always;";
add_header Referrer-Policy "strict-origin-when-cross-origin";
```

# Add New Security Headers

1. Connect to Belden Horizon Data Manager through SSH. Refer to [Access to Belden Horizon Data Manager](docId:9SQxsr4TRIb40AFCXmM5P) for default login credentials. 
2. Open or create the following file: `/etc/nginx/snippets/sec-hdrs.conf`. 
3. If the file exists, run the following command to create a backup by running the copy command. 
   `cp /etc/nginx/snippets/sec-hdrs.conf /etc/nginx/snippets/sec-hdrs.conf.bak`
4. Add or modify the file by using the directives above in *Security Header Directives*.
   - Use the `add_header` directive to add your header. Ensure that each `add_header` statement ends with a semicolon (;).
   - If a header has components separated by semicolons, use double quotation marks ("") to enclose the text. 
5. After editing the file, validate the Nginx configuration with the following command. 
   `sudo nginx -t`
6. If the validation passes without errors, reload Nginx to apply the changes with the following command. 
   `sudo systemctl reload nginx`