[Bug]: modification of cache_usage_limits (ecpu_per_second or data_storage maximum) in aws_elasticache_serverless_cache results in replacement

[mshahmoradi87]

Terraform Core Version

1.5.5

AWS Provider Version

5.40.0

Affected Resource(s)

aws_elasticache_serverless_cache

Expected Behavior

Change in limits should not destroy and recreate the cache, but just change the limit

Actual Behavior

if I change a limit, TF replaces the module, resulting in destroy and creation of the cache.

Relevant Error/Panic Output Snippet

No response

Terraform Configuration Files

resource "aws_elasticache_serverless_cache" "example" {
  engine = "redis"
  name = "example"
  
  cache_usage_limits {
    data_storage {
      maximum = 1
      unit = "GB"
    }

    ecpu_per_second {
      maximum = 1000
    }
  }

  daily_snapshot_time = "09:00"
  description = "Test Server"
  kms_key_id = aws_kms_key.test.arn
  major_engine_version = "7"
  snapshot_retention_limit = 1
  security_group_ids = [aws_security_group.test.id]
  subnet_ids = aws_subnet.test[*].id
}

Steps to Reproduce

• create a redics cache and change one or both of the data_storage and ecpu and apply

Debug Output

No response

Panic Output

No response

Important Factoids

No response

References

No response

Would you like to implement a fix?

No

[github-actions]

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[emdneto]

I'm not sure if it's a bug, as this is defined here.

However, I agree that we don't need to replace the resource when changing the cache_usage_limits since AWS allows to change the limits with in-place updates.

Can anyone tell me if we really need RequiresReplace() for this case? If not, I can fix by removing this to allow update in-place when we set limits.

[mshahmoradi87]

I'm not sure if it's a bug, as this is defined here.

However, I agree that we don't need to replace the resource when changing the cache_usage_limits since AWS allows to change the limits with in-place updates.

Can anyone tell me if we really need RequiresReplace() for this case? If not, I can fix by removing this to allow update in-place when we set limits.

Thanks for checking , it does not need to be replaced and in aws console you can change the limits.
however this has been added here , to fix the previous bug #35897 , and produced this new bug.

[mshahmoradi87]

I'm not sure if it's a bug, as this is defined here.

However, I agree that we don't need to replace the resource when changing the cache_usage_limits since AWS allows to change the limits with in-place updates.

Can anyone tell me if we really need RequiresReplace() for this case? If not, I can fix by removing this to allow update in-place when we set limits.

@ewbankkit can you help to answer this question please.

[mshahmoradi87]

@justinretzolk any chance this gets some attention please ?

[github-actions]

Warning

This issue has been closed, meaning that any additional comments are hard for our team to see. Please assume that the maintainers will not see them.

Ongoing conversations amongst community members are welcome, however, the issue will be locked after 30 days. Moving conversations to another venue, such as the AWS Provider forum, is recommended. If you have additional concerns, please open a new issue, referencing this one where needed.

[github-actions]

This functionality has been released in v5.58.0 of the Terraform AWS Provider. Please see the Terraform documentation on provider versioning or reach out if you need any assistance upgrading.

For further feature requests or bug reports with this functionality, please create a new GitHub issue following the template. Thank you!

[github-actions]

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 have found a problem that seems similar to this, please open a new issue and complete the issue template so we can capture all the details necessary to investigate further.