Route53 ARecord ID change causing "resource already exists" error on redeployment

[patrickufer]

Hi all. We recently bumped cdk-nextjs from v4.0.0-beta.10 to v4.0.0-beta.25 and are getting the following error on redeployment:

3:44:34 PM | CREATE_FAILED        | AWS::Route53::RecordSet                         | Nextjs/Domain/AaaaRecordMain
[Tried to create resource record set [name='some.domain.com.', type='AAAA'] but it already exists]
3:44:34 PM | CREATE_FAILED        | AWS::Route53::RecordSet                         | Nextjs/Domain/ARecordMain
[Tried to create resource record set [name='some.domain.com.', type='A'] but it already exists]

Digging into the how these records are provisioned I noticed the ID for these resources was renamed, causing the issue.
"ARecordMain" vs "AliasRecord"

Obviously we could destroy the stack and solve the issue, but that would cause some downtime in prod.

Anyone have any neat workaround to getting deployments working again without downtime at our Prod URL?

[patrickufer]

Ahhh just found this deleteExisting override prop in NextjsDomainOverrides:
https://github.com/jetbridge/cdk-nextjs/blob/main/src/generated-structs/OptionalARecordProps.ts#L35-L48

I guess we need to set it to true for one deployment?

[patrickufer]

@bestickley any ideas? 🙏

[bestickley]

@patrickufer, not sure if this will work, but could you try to use a CDK Aspect to rename the logical id that's changed back to what it originally was so that CloudFormation doesn't try to re-create?

[patrickufer]

Hmm I'm not well versed with CDK Aspect. IConstruct.id is readonly so no-can-do, right?

export class RenameDNSRecords implements IAspect {
  visit(node: IConstruct): void {
    if (node instanceof RecordSet) {
      node.node.id = 'oldName' // ts error: Cannot assign to 'id' because it is a read-only property.
    }
  }
}

[patrickufer]

@bestickley Another approach that might work would be to bump aws-cdk-lib version to latest to let us set weighted routing on the DNS records (weighted routing was only added to cdk in v2.122.0). Then set weight of the new ARecord and AAAARecord to 1 as well as the existing records so they split traffic evenly. Deployment should work since the identical records can coexist if set to weighted routing.
Concept explained way better here: https://stackoverflow.com/questions/48832132/cloudformation-route53-update-an-existing-recordset

[bestickley]

@patrickufer, ah ok that might not work. I thought logicalId might be different than node id?
Can you update cdk version in your project?

[patrickufer]

@bestickley I'm having some trouble running yarn projen to upgrade cdk in my fork of cdk-nextjs. I get the error

AggregateError: jsii assembly cdk-nextjs-standalone not found

I'm on yarn v1.22.21, maybe it's not compatible?

[bestickley]

I've seen the error before. Try yarn build first.

[patrickufer]

My bad, it's clearly explained in the contribution README to run yarn compile first. Just need to read 😵‍💫

[patrickufer]

With latest v4.0.0-beta-.28 of cdk-nextjs you can add weight property to A and AAAA Record override props like so

nextjsDomain: {
  aRecordProps: {
    weight: 1,
    setIdentifier: 'green'
  },
  aaaaRecordProps: {
    weight: 1,
    setIdentifier: 'green'
  }
}

So first in AWS console you set the existing identical A and AAAA records to weighted with weight: 1. Give them record ID whatever you want, I used 'blue'. Then deploy your stack with weight overrides. This will create identical A and AAAA Records, and split traffic between the old and new evenly. Then you can safely delete the old (blue) A and AAAA records from the AWS Route53 console, and redeploy without the weight overrides!

[bestickley]

Great work, @patrickufer! Would you be open to creating a PR and maybe adding a docs/how-to.md with a section "## Route 53 Traffic Splitting with Weights"? I think this would be helpful to document for future devs! :)