The domain module configures AWS Route53 hosted zones and DNS records for a domain, including apex domain aliasing, wildcard records, and email configuration for both Mailgun and Gmail.
Overview
This module provisions:
- Route53 hosted zone for the domain
- Apex domain A record (aliased to Traefik load balancer)
- Wildcard CNAME record for subdomains
- SPF TXT record for email authentication
- Mailgun CNAME record for email routing
- Gmail MX records for email delivery
The domain name to configure. This will be used to create the Route53 hosted zone.
DNS name of the Traefik load balancer. The apex domain will be aliased to this load balancer.
Zone ID of the Traefik load balancer. Required for creating the alias record.
Outputs
The Route53 zone ID of the created hosted zone. This can be used by other modules to create additional DNS records.
Resources Provisioned
Hosted Zone
resource "aws_route53_zone" "domain" {
name = var.domain
}
Apex Domain Record
resource "aws_route53_record" "apex-domain" {
zone_id = aws_route53_zone.domain.zone_id
name = ""
type = "A"
alias {
name = var.traefik_lb_name
zone_id = var.traefik_zone_id
evaluate_target_health = false
}
}
example.com) that aliases to the Traefik load balancer.
Wildcard Record
resource "aws_route53_record" "wildcard" {
zone_id = aws_route53_zone.domain.zone_id
name = "*"
type = "CNAME"
ttl = 3600
records = [aws_route53_zone.domain.name]
}
*.example.com) pointing to the apex domain, allowing all subdomains to resolve.
Email Configuration
SPF Record
resource "aws_route53_record" "spf" {
zone_id = aws_route53_zone.domain.zone_id
name = ""
type = "TXT"
ttl = 3600
records = ["v=spf1 include:mailgun.org ~all"]
multivalue_answer_routing_policy = true
set_identifier = "spf"
}
Mailgun CNAME
resource "aws_route53_record" "mailgun" {
zone_id = aws_route53_zone.domain.zone_id
name = "email"
type = "CNAME"
ttl = 3600
records = ["mailgun.org."]
}
email.example.com.
Gmail MX Records
resource "aws_route53_record" "gmail" {
zone_id = aws_route53_zone.domain.zone_id
name = ""
type = "MX"
ttl = 3600
records = [
"5 gmr-smtp-in.l.google.com.",
"10 alt1.gmr-smtp-in.l.google.com.",
"20 alt2.gmr-smtp-in.l.google.com.",
"30 alt3.gmr-smtp-in.l.google.com.",
"40 alt4.gmr-smtp-in.l.google.com.",
]
}
Usage Example
module "domain" {
source = "./modules/domain"
domain = "pennlabs.org"
traefik_lb_name = "a1b2c3d4e5f6.us-east-1.elb.amazonaws.com"
traefik_zone_id = "Z35SXDOTRQ7X7K"
}
# Use the zone_id output
resource "aws_route53_record" "custom" {
zone_id = module.domain.zone_id
name = "api"
type = "CNAME"
ttl = 300
records = ["api-backend.example.com"]
}
Dependencies
This module requires:
- AWS provider configured with appropriate credentials
- Existing Traefik load balancer (zone ID and DNS name)
Notes
- The wildcard record uses a TTL of 3600 seconds (1 hour)
- Email records support both Mailgun (for transactional emails) and Gmail (for mailbox hosting)
- The apex domain uses an alias record rather than a CNAME to comply with DNS standards
- All email-related records use a 3600 second TTL