Setting Up Your Own DNS-over-HTTPS Server: A Comprehensive Guide

DNS-over-HTTPS (DoH) offers enhanced privacy and security compared to traditional DNS queries by encrypting your DNS requests. While many public DoH services exist, running your own server provides ultimate control and customization. This guide walks you through setting up your own DoH server, covering various aspects from choosing the right software to configuring it for optimal performance and security.

Choosing the Right Software

Several open-source projects offer robust DoH server implementations. Popular choices include:

• Unbound: A widely-used, highly configurable DNS resolver that supports DoH. Known for its speed and security features.
• coredns: A fast and flexible DNS server written in Go. It offers excellent extensibility and supports various protocols, including DoH.
• dnsmasq: A lightweight and versatile DNS forwarder and DHCP server. While not primarily designed for DoH, it can be configured to offer this functionality.

The best choice depends on your technical expertise and specific requirements. For beginners, dnsmasq might be easier to set up, while Unbound and coredns offer more advanced features and customization options.

Setting up Unbound (Example)

This section details setting up a DoH server using Unbound. Remember to adapt these instructions to your specific system and configuration.

1. Installation:

Install Unbound using your system's package manager. For example, on Debian/Ubuntu:

sudo apt update

sudo apt install unbound

2. Configuration:

Unbound's configuration file is typically located at /etc/unbound/unbound.conf. You'll need to add or modify the following directives:

listen-on-v6: 0.0.0.0#53  #IPv4 listening address

listen-on: 0.0.0.0#53 # IPv6 listening address

interface: 0.0.0.0  #Listen on all interfaces

do-https: yes

https-port: 853  # Custom HTTPS Port

tls-cert: /path/to/your/certificate.pem

tls-private-key: /path/to/your/private.key

Replace placeholders with your actual paths. You'll need to generate a self-signed certificate or obtain a certificate from a trusted Certificate Authority (CA).

3. Restart Unbound:

sudo systemctl restart unbound

Security Considerations

Security is paramount when running a DNS server. Here are crucial aspects:

• Strong Certificates: Use properly generated and managed TLS certificates to encrypt your DoH traffic. Avoid self-signed certificates in production environments unless you understand the implications.
• Firewall Rules: Configure your firewall to allow only necessary traffic to your DoH server on port 853 (HTTPS). Block all other ports for enhanced security.
• Regular Updates: Keep your Unbound (or chosen software) and operating system updated with the latest security patches.
• Resource Limits: Implement resource limits to prevent denial-of-service attacks.
• Auditing: Monitor your server's logs for any suspicious activity.

Client Configuration

Once your server is running, you need to configure your clients (computers, smartphones, etc.) to use your DoH server. This usually involves specifying the DoH endpoint in your operating system's network settings or within your DNS client software. The endpoint will typically look like: https://your-server-ip:853/dns-query

Conclusion

Setting up your own DoH server offers significant privacy and control advantages. While it involves some technical configuration, the enhanced security and customization justify the effort. Remember to prioritize security throughout the process and choose a solution that aligns with your technical skills and needs.