Amazon Route 53 –

📘 Part 1: Introduction to Amazon Route 53

What is Route 53?

Amazon Route 53 is a scalable and highly available Domain Name System (DNS) web service.

Why "Route 53"?

• Named after port 53, the port used for DNS queries.

Key Features:

• Domain registration
• DNS routing
• Health checking & failover

Use Cases:

• Map domain names to AWS services (EC2, S3, ELB, CloudFront)
• Implement high availability and load balancing
• Hybrid cloud DNS resolution

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🌐 Part 2: Core Concepts

1. Domain Name System (DNS)

• Translates domain names (like example.com) to IP addresses

2. Hosted Zone

• A container for records related to a domain (like a DNS zone file)
• Two types:
  • Public Hosted Zone: For internet-facing domains
  • Private Hosted Zone: For internal AWS resources (VPC)

3. Record Sets (DNS Records)

• Types:
  • A Record: Maps domain to an IPv4 address
  • AAAA Record: Maps domain to an IPv6 address
  • CNAME: Alias to another domain name
  • MX: Mail exchange
  • NS: Name servers for the domain
  • SOA: Start of authority
  • TXT: Text records (e.g., verification)
  • Alias: AWS-specific (e.g., S3, ELB)

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🔁 Part 3: Routing Policies

Routing Policy	Use Case	Description
Simple	Single resource	Basic IP or Alias mapping
Weighted	A/B Testing or load balancing	Assign weights to resources
Latency	Geo latency-based optimization	Direct to region with lowest latency
Failover	High availability setups	Primary/secondary failover based on health check
Geolocation	Region-specific content	Route based on user’s geographic location
Geoproximity (Traffic Flow)	Advanced regional routing	Bias traffic toward regions (requires Traffic Flow)
Multi-value answer	Basic round-robin	Returns multiple healthy IPs

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🛠️ Part 4: Hands-On Lab – Host a Website Using Route 53

Objective:

Host a static website in S3 and use Route 53 to point your domain to it.

Prerequisites:

• Registered domain (can be via Route 53 or external provider)
• S3 bucket with static website

Steps:

1. Create an S3 Bucket (static website)

• Bucket name must match your domain (e.g., mydomain.com)
• Enable Static website hosting
• Upload index.html

2. Create a Hosted Zone

• Go to Route 53 > Hosted Zones > Create Hosted Zone
• Type: Public Hosted Zone
• Domain: mydomain.com

3. Create an Alias Record

• Go to Record sets > Create Record
• Name: (leave blank for root domain)
• Type: A – IPv4 address
• Alias: Yes → Choose S3 endpoint from drop-down

4. Update Name Servers at Registrar

• If domain is external:
  • Copy NS records from Route 53
  • Update them at domain registrar

5. Access Website

• Navigate to http://mydomain.com

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💼 Part 5: Real-Time Use Case – Regional Web Failover

Objective:

Serve traffic from primary EC2 in us-east-1, and failover to EC2 in us-west-2 during outage.

Steps:

1. Setup Two EC2 Instances

• One in us-east-1 and one in us-west-2
• Install web server and custom index page (e.g., "Primary" vs "Backup")

2. Create Two A Records

• Use Failover routing policy
• Set up health check on primary EC2 (TCP or HTTP)

3. Test

• Stop primary EC2 or fail health check
• Route 53 automatically routes to secondary

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📈 Part 6: Pricing & Limits

Pricing:

• Hosted zone: $0.50/month per zone
• Queries: $0.40/million for first 1B queries
• Health checks: ~$0.50/month

Limits:

• 500 domain names per AWS account (can increase)
• 10,000 records per hosted zone (soft limit)

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🧠 Part 7: Tips & Best Practices

• Use Alias Records for AWS resources (no extra cost)
• Monitor DNS with CloudWatch metrics
• Use TTLs appropriately (shorter for failover scenarios)
• Use private hosted zones for internal-only DNS (e.g., VPC service discovery)
• Document all health checks and failover policies

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❓ Part 8: Q&A and Wrap-up

• Discuss custom routing scenarios
• Real-world examples from participants
• Link Route 53 with CloudFront, S3, or EC2 for full stack hosting

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End of Session