# Use existing target group for ALB event

**URL:** <https://forum.serverless.com/t/use-existing-target-group-for-alb-event/16571>\
**Category:** Serverless Framework\
**Tags:** aws, cloudformation\
**Created:** [January 17, 2022, 11:08am UTC](https://forum.serverless.com/t/use-existing-target-group-for-alb-event/16571 "2022-01-17T11:08:44Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![AdamA](https://avatars.discourse-cdn.com/v4/letter/a/53a042/32.png) [@AdamA](https://forum.serverless.com/u/AdamA)\
**Post date:** [January 17, 2022, 11:08am UTC](https://forum.serverless.com/t/use-existing-target-group-for-alb-event/16571/1 "2022-01-17T11:08:44Z")

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Hi folks

I’m trying a deploy a lambda which is to be triggered by an ALB, but I’m getting tripped up by the target group. I can’t find a way to specify an existing one, as providing a name just complains that it already exists, and when creating a new one CloudFormation fails with the following error:  
API: elasticloadbalancingv2:RegisterTargets elasticloadbalancing principal does not have permission to invoke from target group

Is it possible for me to use an existing target group? If not, what is this principal I need to fix and how do I do it please? Haven’t really used AWS CLI much before.

TIA!

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<div class="post-metadata">

**Author:** ![AdamA](https://avatars.discourse-cdn.com/v4/letter/a/53a042/32.png) [@AdamA](https://forum.serverless.com/u/AdamA)\
**Post date:** [January 20, 2022, 11:10am UTC](https://forum.serverless.com/t/use-existing-target-group-for-alb-event/16571/2 "2022-01-20T11:10:42Z")

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Solution was just to add an IAM role statement to the yaml:

```auto
iamRoleStatements:
    - Effect: Allow
      Action:
        - elasticloadbalancingv2:RegisterTargets
      Resource: ${env:AWS_ALB_ARN}

```