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---
title: DNS Architecture
description: Core DNS architecture patterns for self-hosted and homelab environments
tags:
- dns
- networking
- infrastructure
category: networking
created: 2026-03-14
updated: 2026-03-14
---
# DNS Architecture
## Summary
DNS architecture defines how names are assigned, resolved, delegated, and operated across internal and external systems. In self-hosted environments, good DNS design reduces configuration drift, improves service discoverability, and simplifies remote access.
## Why it matters
DNS is a foundational dependency for reverse proxies, TLS, service discovery, monitoring, and operator workflows. Weak DNS design creates brittle systems that depend on hard-coded IP addresses and manual recovery steps.
## Core concepts
- Authoritative DNS: the source of truth for a zone
- Recursive resolution: the process clients use to resolve names
- Internal DNS: records intended only for private services
- Split-horizon DNS: different answers depending on the client context
- TTL: cache lifetime that affects propagation and change speed
## Practical usage
A practical self-hosted DNS model often includes:
- Public DNS for internet-facing records
- Internal DNS for management and private services
- Reverse proxy hostnames for application routing
- Stable names for infrastructure services such as hypervisors, backup targets, and monitoring systems
Example record set:
```text
proxy.example.net A 198.51.100.20
grafana.internal.example A 192.0.2.20
gitea.internal.example CNAME proxy.internal.example
```
## Best practices
- Use DNS names instead of embedding IP addresses in application config
- Separate public and private naming where trust boundaries differ
- Keep TTLs appropriate for the change rate of the record
- Treat authoritative DNS as critical infrastructure with backup and access control
## Pitfalls
- Reusing the same name for unrelated services over time
- Forgetting that split DNS can confuse troubleshooting if undocumented
- Leaving DNS ownership unclear across platforms and providers
- Building service dependencies on local `/etc/hosts` entries
## References
- [Cloudflare Learning Center: What is DNS?](https://www.cloudflare.com/learning/dns/what-is-dns/)
- [RFC 1034: Domain Concepts and Facilities](https://www.rfc-editor.org/rfc/rfc1034)
- [RFC 1035: Domain Implementation and Specification](https://www.rfc-editor.org/rfc/rfc1035)