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aws-elasticloadbalancingv2: Resource of type 'AWS::ElasticLoadBalancingV2::Listener' with identifier 'Idempotency Check Failed' already exists.

See original GitHub issue

❓ General Issue

The Question

We are trying to run our cloudformation template to modify our environment but keep getting this error:

Resource of type 'AWS::ElasticLoadBalancingV2::Listener' with identifier 'Idempotency Check Failed' already exists.


  • CDK CLI Version: Not using
  • Module Version: 1.89.0
  • Node.js Version: 14.15.4
  • OS: Ubuntu 18.04.5 LTS
  • Language (Version): TypeScript 3.9.7

Other information

Here is the load balancer related code:

import * as elb from '@aws-cdk/aws-elasticloadbalancingv2';

const loadBalancer = new elb.ApplicationLoadBalancer(this, 'Alb', {
            vpc: props.vpc,
            internetFacing: true

const listener = loadBalancer.addListener(`PublicListener`, {
            protocol: elb.ApplicationProtocol.HTTPS,
            port: 443,
            open: true,
            defaultAction: elb.ListenerAction.fixedResponse(200, {
                contentType: 'text/html',
                messageBody: `<html><head><title>Load Balancer</title></head><body>${this.namespace}</body></html>`

listener.addCertificates('Arns', [elb.ListenerCertificate.fromCertificateManager(props.certificate)]);

loadBalancer.addListener('PublicRedirectListener', {
            protocol: elb.ApplicationProtocol.HTTP,
            port: 80,
            open: true,
            defaultAction: elb.ListenerAction.redirect({
                port: '443',
                protocol: elb.ApplicationProtocol.HTTPS,
                permanent: true,

Here is the actual error from CloudFormation:


The listener in question (HTTPS listener) already exists so CloudFormation should just keep going as we are just updating some other resources.

Here is a picture of the listener that already exists:


Issue Analytics

  • State:closed
  • Created 3 years ago
  • Reactions:3
  • Comments:9 (2 by maintainers)

github_iconTop GitHub Comments

peterwoodworthcommented, Aug 4, 2021

I was able to reproduce this issue. According to CloudFormation, if the arn of the Listener is updated (this would happen if you change the id) then a replacement of the resource will need to happen. When cloudformation replaces a resource, it will first create the replacement resource then delete the old resource. This will cause a failure during deployment because it will try to create a Listener with a port that’s already being used by the listener (despite the fact that the listener already using the port would be about to be deleted).

To fix this, you’ll want to either adjust your code so that CFN doesn’t think it needs to recreate your resource, or if you want to keep your configuration the way it currently I’m not sure what the best way to solve this would be. If deleting just the listener doesn’t cause any issues that could potentially work. If you figure a way out of this situation let me know, and if you need additional help or guidance, feel free to ping me 😄

chungllai2commented, Mar 20, 2022

I am using elastic beanstalk & having the same error.

TLDR: If you create the ALB manually, don’t try to update the config with cloudformation file

@peterwoodworth is right, on my case, I create the Load balancer MANUALLY on elastic beanstalk management console.

When I updated it with a .ebextensions/alb-http-to-https-redirection-full.config, it will prompt this error

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