Hi @vcschapp , thansk for reaching out.

I see the related issue of configuring cross-zone load balancing false for ALB target groups has been discussed here in detail s-#29866 (comment)

and a corresponding Workaround was also suggested for target groups-#29866 (comment).
There is a PR submissions as well- crossZoneEnabled does not support false for ALB.

Request you to take a look and get back if this does not solve the usecase you are referring to.

@khushail thanks.

The issue you referenced is not related (#31790) and the PR you referenced does not fix the problem (#29907).

In issue #31790, the user is requesting to turn off cross-zone at the ALB level, which is not possible.

The workaround indicated by codypenta@ doesn't work for me in general because, as I mentioned in the main issue text:

In theory, you can workaround this issue in CDK using the CfnTargetGroup.addOverride. However, because adding overrides would entirely replace the values CDK wants to put for the target group attributes, in practice this means adding overrides would force me to replicate CDK's entire logic for target group attributes.

My understanding of the code in CfnResource.addOverride is that there is no way to supplement keys added by CDK. If you use addOverride you are replacing what CDK puts there.

The description for PR #29907 says:

This PR covers the following cases:

...

3/ When crossZoneEnabled is false with ALB, cdk throws an error because ALB does not support disabling it per doc description.

So basically the PR makes CDK throw an exception when you try to turn off cross-zone for ALB at the load balancer level. This is fine, as ALB doesn't support that. But that's not what my issue is about. My issue is about disabling cross-zone at the target group level, which ALB does support, and CloudFormation supports, but CDK does not.

@vcschapp , thanks so much for explaining that so well and getting back.

I understood your point and confirm that its supported by cloudformation as well - https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/aws-properties-elasticloadbalancingv2-targetgroup-targetgroupattribute.html#cfn-elasticloadbalancingv2-targetgroup-targetgroupattribute-key

So till it is implemented , as a workaround, this should be achievable with Escape hatches using L1 construct.

I would be marking this as P2 which means it won't be immediately addresed by the team but would be on their radar and for keeping it open for contribution from community as well as from the team as well.

Thanks.

Thanks @khushail, I appreciate the updates.

Btw, it looks like @mazyu36 already has a PR out to potentially fix it!

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