DNS Management

Table of Contents

• [Overview](#overview)
• [When to Use](#when-to-use)
• [Quick Start](#quick-start)
• [Reference Guides](#reference-guides)
• [Best Practices](#best-practices)

Overview

Implement DNS management strategies for traffic routing, failover, geo-routing, and high availability using Route53, Azure DNS, or CloudFlare.

When to Use

• Domain management and routing
• Failover and disaster recovery
• Geographic load balancing
• Multi-region deployments
• DNS-based traffic management
• CDN integration
• Health check routing
• Zero-downtime migrations

Quick Start

Minimal working example:

# route53-setup.yaml
apiVersion: v1
kind: ConfigMap
metadata:
  name: route53-config
  namespace: operations
data:
  setup-dns.sh: |
    #!/bin/bash
    set -euo pipefail

    DOMAIN="myapp.com"
    HOSTED_ZONE_ID="Z1234567890ABC"
    PRIMARY_ENDPOINT="myapp-primary.example.com"
    SECONDARY_ENDPOINT="myapp-secondary.example.com"

    echo "Setting up Route53 DNS for $DOMAIN"

    # Create health check for primary
    PRIMARY_HEALTH=$(aws route53 create-health-check \
      --health-check-config '{
        "Type": "HTTPS",
        "ResourcePath": "/health",
        "FullyQualifiedDomainName": "'${PRIMARY_ENDPOINT}'",
        "Port": 443,
// ... (see reference guides for full implementation)

Reference Guides

Detailed implementations in the references/ directory:

Best Practices

✅ DO

• Use health checks with failover
• Set appropriate TTL values
• Implement geolocation routing
• Use weighted routing for canary
• Monitor DNS resolution
• Document DNS changes
• Test failover procedures
• Use DNS DNSSEC

❌ DON'T

• Use TTL of 0
• Point to single endpoint
• Forget health checks
• Mix DNS and application failover
• Change DNS during incidents
• Ignore DNS propagation time
• Use generic names
• Skip DNS monitoring