Google Compute Forward Rule creation failure when ports list longer than five items

[owensk]

Terraform Version

Terraform v0.9.3

Affected Resource(s)

• google_compute_forwarding_rule

Terraform Configuration Files

resource "google_compute_forwarding_rule" "linkerd-more-ports-forwarding-rule" {
  name                  = "linkerd-more-ports-forwarding-rule"
  backend_service       = "${google_compute_region_backend_service.linkerd-regional-backend-service.self_link}"
  ports                 = ["7002","7004","7007","7011","7019","7021","7029"]
  load_balancing_scheme = "INTERNAL"
}

Debug Output

Plan output:

+ module.linkerd-prod.google_compute_forwarding_rule.linkerd-more-ports-forwarding-rule
    backend_service:       "https://www.googleapis.com/compute/v1/projects/olark-main/regions/us-central1/backendServices/linkerd-regional-backend-service"
    ip_address:            "<computed>"
    ip_protocol:           "<computed>"
    load_balancing_scheme: "INTERNAL"
    name:                  "linkerd-more-ports-forwarding-rule"
    network:               "<computed>"
    ports.#:               "7"
    ports.2135072231:      "7002"
    ports.2518759634:      "7004"
    ports.254306664:       "7007"
    ports.3565006559:      "7021"
    ports.3668322029:      "7029"
    ports.4052448558:      "7019"
    ports.4283497756:      "7011"
    project:               "<computed>"
    region:                "<computed>"
    self_link:             "<computed>"
    subnetwork:            "<computed>"

Apply Ouput:

Error applying plan:

1 error(s) occurred:

* module.linkerd-prod.google_compute_forwarding_rule.linkerd-more-ports-forwarding-rule: 1 error(s) occurred:

* google_compute_forwarding_rule.linkerd-more-ports-forwarding-rule: Error creating ForwardingRule: googleapi: Error 400: Invalid value for field 'resource.ports[5]': '7019'. Too many ports specified. Maximum is 5., invalid

Expected Behavior

Should create forwarding rule that forwards listed ports to all instances in backend.

Actual Behavior

Doesn't create anything on apply. plan doesn't fail because too many ports listed.

Steps to Reproduce

Please list the steps required to reproduce the issue, for example:

1. Setup forwarding rule to look like config give
2. terraform plan to see change
3. terraform apply to attempt change

Important Factoids

Neither TerraForm or Google Cloud Compute Forwarding rules documentation specify an upper limit of 5 ports on an internal forwarding rule.

[danawillow]

Hey @owensk, I see at https://cloud.google.com/compute/docs/reference/latest/forwardingRules that a maximum of 5 ports can be specified. Can you point me to where else within GCP you expected to see that documented? In the meantime, I can fix the terraform documentation and throw an error in the plan stage.

[owensk]

Apparently, I missed that location when I was looking around to solve this problem. I think updating TerraForm docs and throwing an error in plan are an acceptable solution.

[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.

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