ELB creation with multiple subnets in the same AZ cause "Default VPC not found" error

[hashibot]

This issue was originally opened by @harpermann as hashicorp/terraform#15899. It was migrated here as a result of the provider split. The original body of the issue is below.

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Hi Hashicorp,
Terraform is great stuff. We're using it a ton. We found a minor bug were we get a misleading error message.

Terraform Version

** terraform -v = Terraform v0.9.8 **

Terraform Configuration Files

**ELB with multiple subnets in same AZ in subnet ids**
resource "aws_elb" "jenkins" {
  name               = "elb-jenkins-${var.dp_env}"
  #availability_zones = [  "us-west-2a", "use-west-2b", "us-west-2c" ]
  subnets            = [ "subnet-xxxxxxx", "subnet-xxxxxxxx", "subnet-xxxxxxxx", "subnet-xxxxxxxx", "subnet-xxxxxxx" ]
  security_groups    = [
    "${var.sg_app_elb}",
    "${var.sg_app_elb_ppd_apigw}",
    "${var.sg_app_elb_prd_apigw}",
    "${var.sg_app_elb_perf_portal}"
  ]

Debug Output

• use subnets or availability_zones but not both on ELB Create. (with subnets defined and multiple subnets in the same AZ, and availability_zones commented out)
• InvalidConfigurationRequest: Default VPC not found (with subnets commented and using only avaiability_zones)
• Failure adding ELB subnets: InvalidConfigurationRequest: ELB cannot be attached to multiple subnets in the same AZ" (after creating ELB with subnets with one subnet per AZ, no availability_zones, then updating with multiple subnets in same AZ)

Crash Output

not crashing

Expected Behavior

**On ELB create with multiple subnets in the same AZ, should get error:
Failure adding ELB subnets: InvalidConfigurationRequest: ELB cannot be attached to multiple subnets in the same AZ
**

Actual Behavior

Got misleading "Default VPC not found" error

Steps to Reproduce

• If we use only the subnets (some in same AZ), we get an error saying either we need to use subnets or availability_zones but not both on ELB Create.
• if we coment out subnets and use 3 AZ's, we get the error on ELB Create: InvalidConfigurationRequest: Default VPC not found
• If we start with 3 subnets not in multi AZ's ELB create works.
• if we add 3 more subnets in same AZ's for a total of 6, we get " Failure adding ELB subnets: InvalidConfigurationRequest: ELB cannot be attached to multiple subnets in the same AZ"
• This is likely the error we want in the first case.

Important Factoids

Are there anything atypical about your situation that we should know? For example: is Terraform running in a wrapper script or in a CI system? Are you passing any unusual command line options or environment variables to opt-in to non-default behavior?

• We run with a wrapper script, but this is TF configuration and not caused by the script.

References

Looked but couldn't find related issues.

[kmcquade]

+1

[github-actions]

Marking this issue as stale due to inactivity. This helps our maintainers find and focus on the active issues. If this issue receives no comments in the next 30 days it will automatically be closed. Maintainers can also remove the stale label.

If this issue was automatically closed and you feel this issue should be reopened, we encourage creating a new issue linking back to this one for added context. Thank you!

[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!