route53-sidecar

Sidecar that adds a route53 record on container start, removes it on SIGHUP shutdown.

1. Takes the IP address from EC2 or ECS metadata (or IPADDRESS environment)
2. Creates a weighted A record pointing to DNS with TTL DNSTTL in the HOSTEDZONE
3. When SIGHUP happens, it removes the created record
4. Then waits for the record to SYNC in route53 servers
5. Finally it waits for DNS TTL time to expire
6. Then exits 0

Environment variables:

• IPADDRESS The ip address, or set as public-ipv4 (default) to get it from instance metadata, ecs to get it from ECS container metadata
• DNS The fully qualified DNS name to set
• DNSTTL The TTL time for the DNS A record entry (default 10 seconds)
• HOSTEDZONE The AWS Route53 Hosted Zone ID

Test from command line:

make build
./route53-sidecar -dns="test.example.com" -hostedzone=ABCDEFGHIJKLM4 -ipaddress=127.0.0.1

Use the existing docker image locally:

docker run -v ~/.aws:/root/.aws discobean/route53-sidecar -dns="test.example.com" -hostedzone=ABCDEFGHIJKLM4 -ipaddress=127.0.0.1

Build your own docker image:

make docker

Policies required for AWS ECS Role:

- PolicyName: route53
  PolicyDocument:
    Statement:
    - Effect: Allow
      Action:
        - route53:ChangeResourceRecordSets
      Resource: !Sub arn:aws:route53:::hostedzone/${HOSTEDZONEID}
- PolicyName: route53changes
  PolicyDocument:
    Statement:
    - Effect: Allow
      Action:
        - route53:GetChange
      Resource: "*"