Elasticache cluster mode multiAZ issue

[hashibot]

This issue was originally opened by @piggybankwang as hashicorp/terraform#15653. It was migrated here as a result of the provider split. The original body of the issue is below.

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PROVIDER ISSUES

Used terraform 0.9.11

Error msg: aws_elasticache_replication_group.**cache_cluster: Error creating Elasticache Replication Group: InvalidParameterCombination: PreferredCacheClusterAZs can only be specified for one node group.
status code: 400, request id: 128e19df-7306-11e7-bb09-378be33ea9ac

I think the issue is, to support multiAZ, for cluster mode elasticache, each shard requires an availability zone.
From terraform
the availability_zones is a set not a list, so it doesn't allow duplicates

PLEASE NOTE: Terraform has split out the builtin Providers into their own repositories. For any Provider issues, please open all issues and pull requests in the corresponding repository. An index of supported Providers can be found here:

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All other issues (that appear to affect multiple or all providers) may be an issue with Terraform's core, and should be opened here.

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Hi there,

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• Make aws_iam_policy_attachment warning less opaque #1234

[bflad]

From the original issue report:

From terraform
the availability_zones is a set not a list, so it doesn't allow duplicates

This was fixed with the addition of the preferred_availability_zones argument in version 1.23.0 of the AWS provider and has been available in all releases since. Please see the Terraform documentation on provider versioning or reach out if you need any assistance upgrading.

[widgetpl]

I think there is the same issue for aws_elasticache_replication_group:

Error: Error applying plan:

1 error(s) occurred:

* module.redis.aws_elasticache_replication_group.redis: 1 error(s) occurred:

* aws_elasticache_replication_group.redis: Error creating Elasticache Replication Group: InvalidParameterCombination: PreferredCacheClusterAZs can only be specified for one node group.
	status code: 400, request id: b659f391-8200-11e9-8d64-fd148c7106cf

Terraform does not automatically rollback in the face of errors.
Instead, your Terraform state file has been partially updated with
any resources that successfully completed. Please address the error
above and apply again to incrementally change your infrastructure.

[mbolek]

@widgetpl it works when you do not supply the "availability_zones" parameter at all.
@bflad should this be reopened then? terraform docs suggest the availability_zones are optional but I believe it should work when supplied

[Codonaut]

Just wanted to chime in that I'm also experiencing the issue that @widgetpl reported. @bflad should we re-open this, or should I create a new issue for aws_elasticache_replication_group?

[ghost]

I'm going to lock this issue because it has been closed for 30 days ⏳. This helps our maintainers find and focus on the active issues.

If you feel this issue should be reopened, we encourage creating a new issue linking back to this one for added context. Thanks!